The Programmation Notes

in this book, i will store my notes and snippets of my learning programmation languages, in:

• rust
• c
• bash
• lua
• vim
• js
• flutter
• latex

Basics

clc        % clear command window
clear      % clear memory
;          % no result displayed if command is terminated with semikolon

3.1 Comments

% Single Comment
%{
    multi
    line
    comment!
%}

% MATRICES / VECTORS
ones(3,4)			generate 3x4 matrix filled with ones
zeros(3,4)			generate 3x4 matrix filled with zeros

m = [1,2 ; 3,4]		
[1 2]
[3 4]

m[1,2]	get value of 1st row, 2nd column of matrix m
m[2,:]			generates a vector with values of 2nd row 
v = 1:5			generate vector v = [1 2 3 4 5]

numel(x)	counts number of elements in x (works for vectors & matrix)



COMMENTS						
%			code on current line will be ignored
%%			new comment-section



CONSTANTS						
pi			Pi
exp(1)			e^1 (Eulersche Zahl)



FUNCTIONS (anonymous)					
name =@(x) x^2;		define function name=x^2 with x as input
name(2);			computes functionvalue of function name at x=2

name2 =@(a,b) a^2 + b^2;	define function f=a^2+b^2 with a and b as input
name2(2,3);		computes functionvalue of function name2 at 2



IMPLIZIT PLOTS!
ezplot('x.^3 + x.*y + y.^2 - 36',[-10 10 -10 10]);

[x,fval] = fminsearch(@(x)  x(1).^2 + x(2).^2, [2 1])

WRITE TO CONSOLE
fprintf('message with %s', 'asd');
disp('message with asd');

ERROR MESSAGE IN RED
fprintf(2,'my error(warning) message in RED!\n' );

CELLS

C = cell(3,1);                 % initialize cellarray (3x1)
C(1) = cellstr('test1');       % convert string to cellarray
C(3) = cellstr('test2');       % convert string to cellarray
disp(C);                       % display cellarray (1 empty value)
disp(C(~cellfun('isempty',C))  % delete empty entries

% convert cell to string
C = cell({'t1','t2',''});  % generate cell
str1 = char(C(1));         % convert 1st element of cell-array 
str2 = char(C(2));         % convert 2nd element of cell-array 
str3 = char(C(3));         % empty 1-by-0 matrix

2.2 Clearing Data

clc % Clear command window (does not clear variables)
clf % Clear figures

clear % Clear everything
clear all % Clear everything

clear <variable> % Clear single variable

2.3 Configure Output

format compact % Keeps output compact!

2.4 Stop Execution

Use CTRL-c to stop executing a particular command!

2.5 Precision

Precision is set to 15 digits by default. But you can configure that!

3. Basic MATLAB Syntax Reference

Click on New Script to start creating a new script!

3.1 Comments

go to top

% Single Comment

%{
    multi
    line
    comment!
%}

You can also use CTRL-r to comment and CTRL-t to uncomment!

3.2 Variables

Everything is a double by default in MATLAB.

a = 5 % a is now 5! Yay!

Data Types:

• int8, int16, int32, int64
• char
• logical (Booleans)
• double
• single (Value without a decimal place)
• uint8

More On Variables

c1 = 'A'
class(c1) % Prints the class/type of the variable!

s1 = 'A string'
class(s1) % With single quotes, the class is 'char'

s2 = "A string"
class(s2) % With double quotes, the class is 'string'

5 > 2 % Logical 1
b1 = true % Logical 1

To get the maximum number you can store, you can use these! The maximum and minimums differ depending on the number type. The example list I'm writing below is non-exhaustive.

% For ints
intmax('int8')
intmin('int8')

% For doubles
realmax

% For singles
realmax('single')

3.3 Basic Operations

I really shouldn't need to explain this... You can use MATLAB like a calculator, and the results can go into variables!

a = 1 + 2 + 3 + 4 + 5

5 + 5 % Add
5 - 5 % Subtract
5 * 5 % Multiply
5 / 5 % Divide
5 ^ 4 % Exponent
mod(5, 4) % Mod (get remainder)

% NOTE! MATLAB doesn't have increment and decrement operators. So you can't do stuff like a++, b--, etc.

3.4 Casting

v2 = 8
v3 = int8(v2) % Like so!

Just write the appropriate class identifier and use it like a function!

3.5 Printing and Displaying

% Use this to display vectors and numbers!
disp(some_vector_variable)

% Use this to print strings!
fprintf("Hello world!")

% sprintf prints as a string
sprintf('5 + 4 = %d\n', 5 + 4)
% With the %d here, it transplants the next variable argument into the string!

3.6 User Input

Using the ; suppresses the input printout after the user has entered the input!

Note: " might not work in some versions of MATLAB as a string delineator. Use ' in that case.

String Input

% String Input
% Notice the '' escapes the second quote
name = input('What''s your name : ', 's');

% Let's use this if statement to print the input out! (~ means not)
if ~isempty(name)
    fprinf('Hello %s\n', name)
end

Vector Input

vInput = input('Enter a vector : ');
disp(vInput)

3.7 Useful Math Functions

help elfun for a whole list of math functions

randi([10, 20]) % Random int
abs(-1) % Returns 1
floor(2.45) % Returns 2
ceil(2.45) % Returns 3
round(2.45) % Returns 2
exp(1) % e^x
log(100) % Log base e (ln)
log10(100) % Log base 10
log2(100) % Log base 2
sqrt(100) % Square root
deg2rad(90)
rad2deg(3.14)

3.8 Conditionals

> % More than
< % Less than
>= % More than or equal to
<= % Less than or equal to
== % Equal to
~= % Not equal to

|| % Or
&& % And
~ % Not

If block

if <condition>
    <do something>
elseif <condition>
    <do something else>
else
    <do something entirely different>
end % REMEMBER TO END!!!

Switch Statement

switch score
    case 1
        disp("Aw")
    case 2
        disp("Better")
    case 3
        disp("You get the point")
    otherwise
        disp("WHO NAMED IT OTHERWISE OMG")
end % REMEMBER TO END

3.9 Vectors

They're one dimensional rows or columns!

THE INDEXING FOR MATLAB STARTS AT 1, NOT 0!!!!

% Row Vectors
vector_1 = [5 3 2 1] % Yep!
vector_2 [5, 3, 2, 1] % Both are valid ways!

% Column Vectors
vector_3 = [5; 3; 2; 1]

% Index into the vectors
vector_1(1) % 5
vector_1(end) % 1 (Last value)
vector([1 2 3]) % Get first, second, and third value in vector

% Get range
vector_1(1:3) % First to third

% Change at index
vector_1(1) = 6

% Transpose Vector
a = [1 2 3]
a' % This is now 1, 2, 3 as a column!

Vector Operations

a = [2; 3; 4]
b = [1 2 3]

a * b
% 2 4 6
% 3 6 9
% 4 8 2

3.10 Vector Methods

vector_1 = [1 2 3 4 5]
length(vector_1)
sort(vector_1, 'descend')

% Create ranges
5 : 10 % Gives you [5 6 7 8 9 10]
2 : 2 : 10 % Gives you [2 4 6 8 10]

% Concatenate
a = [1 2 3]
b = [4 5 6]
[a b] % [1 2 3 4 5 6]

% Dot Product (Either...)
a * b' % Transpose as needed
dot(a, b) % Self explanatory

% Cross Product
cross(a, b) % Nice

% Linspace
linspace(1, 20, 4) % Generates 4 numbers equally spaced between 1 and 20

% Logspace
logspace(1, 3, 3) % Like linspace, but the spacing is logarithmic

3.11 Matrices

It's MATLAB, not Vector lab.

matrix_a = [2 3 4; 4 6 8] % 2 rows, 3 columns (2x3)

length(matrix_a) % Gets you 3 (columns)
numel(matrix_a) % Number of values in matrix (6)
size(matrix_a) % Rows, then Columns (2 3)

% Generate random matrices!
randi([10, 20], 2)

% Index into matrices
a = [1 2 3; 4 5 6; 7 8 9]

a(1, 2) = 22 % Index into single value
a(1, :) = 25 % Change all row values
a(:, 2) % Change all column values
a(end, 1) % Last row
a(1, end) % Last column

% To delete a value, just literally put a semicolon at the end.
a(1, 2) = ;

% Multiply matrices
a * b

% Element-wise multiplication
a .* b % Take note of the period!

% Other matrix stuffffff
a - b
a + b

3.12 Matrix Methods

The list is not exhaustive!

Construction

Use the help command to find out how these work! They're overloaded functions.

eye()
ones()
zeros()
diag()

Mathematical Operations

sqrt(a) % Square root all values in matrix
sum(a) % Sum all columns
sum(a, 'all') % Sum all entries

prod(a) % Multiply all column values

cumsum(a, 'reverse') % Cumulative sum. First row stays the same, each row after is the sum of the preceding and current row (reverse makes it go in reverse)
cumsum(a) % Or if you don't want it reversed..
cumprod(a) % Cumulative product.

det() % Determinant
inv() % Inverse

Conditionals and Indexing

isequal(a, b) % Check for equality
a > 3 % Apply conditional to all entries
find(a > 24) % Gives you index of entries that fulfill the condition

Transformations

fliplr(a) % Flip left to right
flipud(a) % Flip up down

rot90(a) % Rotate 90 degrees
rot90(a, 2) % Rotate 180 degrees

reshape(a, 2, 6) % Reshape into 2x6, it's like numpy!
repmat(a, 2, 1) % Duplicate matrix into new matrix. Eg. If original matrix was 3x3, doing repmat(a, 2, 1) makes it 6x3

repelem(m3, 2, 1) % Duplicates ELEMENTS, so in this case, each element is duplicated twice in terms of the row

3.13 For Loops

For loops! It's pretty Pythonic. It iterates through a range.

% Loop from 1 to 10 and print it
for i = 1:10
    disp(i)
end % REMEMBER TO END

% MORE EXAMPLES

% Print every value in matrix
a = [1 2 3; 4 5 6]
for i = 1:2
    for j = 1:3
        disp(a(i, j))
    end
end

% Print for undetermined length
b = [6 7 8]
for i = 1:length(b)
    disp(b(i))
end

3.14 While Loops

i = 1 % You must create the variable first!

while i < 20
    if(mod(i, 2)) == 0
        disp(i)
        i = i + 1; % Semicolon suppresses the print
        continue
    end % This end is for i

    i = i + 1;
    if i >= 10
        break
    end
end

3.15 Cell Arrays

You can store data of multiple types

cell_A = {'Hi', 35, [25 8 19]}
cell_B = cell(5) % Create the cell spaces first

cell_A{1} % Get first element
cell_A{3}(2) % Index further
cell_A{4} = 'Something else'
cell_A(4) = ; % Delete

for i = 1:length(cell_A)
    disp(cell_A{i})
end

% You can cast character arrays into cell arrays too!
a = ['A', 'BB', 'CCC']
char_array = cellstr(a)

3.16 Strings

Strings are vectors of characters!

str_1 = 'I am a string'
length(str_1)

% Index into a string
str_1(1)
str_1(3:4) % Slices

% Concatenation
str = strcat(str1, ' and now I''m longer!')

% Look for substring
strfind(str, 'a') % Returns indexes of all found substrings

% Replace string
strrep(str, 'longer', 'bigger')

% Split string
str_array = strsplit(str, ' ') % Splits at all spaces. Makes a string array

% Convert numbers to string
int2str(99)
num2str(3.14)

% Check for equality
strcmp(str1, str2)

% Check if is char
ischar('Rawr!11!!1')

% Check if a string is just made of letters
isletter('num 2') % Logical 0
isstrprop('word2', 'alpha')

% Check if string is made of alphanumeric characters
isstrprop('word2', 'alphanum') % Logical 1

% Sort
sort(str, 'descend')

% Delete whitespace (it's like .strip() in python)
strtrim(str)

% Lower and Uppercase conversion
lower(str)
upper(str)

3.17 Structures

Custom data types! Think C++ structs! Or Python dictionaries/maps.

methyl_struct = struct('name', 'methylDragon', ... % the ... lets you skip down to the next line (:
'species', ' Dragon')

disp(methyl_struct.name) % methylDragon

% Add a new field!
methyl_struct.sound = 'Rawr'

% Delete a field
methyl_struct = rmfield(methyl_struct, 'sound')

% Check if field exists
isfield(methyl_struct, 'species')

% Get all field names
fieldnames(methyl_struct)

% Store structures in vectors!
a(1) = methyl_struct

3.18 Tables

Tables are labelled rows of data in a table format

Get help table if you need help.

a = {'A'; 'B'; 'C'; 'D'};
b = [29; 42; 1; 2]
c = {'AA', 'BB', 'CC', 'DD'}

% Create a table!!! We'll specify a as the index now
test_table = table(a, b, c, 'RowName', a)

% You can do cool stuff with tables!
mean(test_table.b) % For example.. find the means

% Add new fields
test_table.d = [1; 2; 3]

% Pull specific entries
test_table({'A', 'B'}, :) % This defaults to using the RowName as indexer

% Pull specific entries, using another row
a(ismember(test_table.b, {29, 42},:)

3.19 File IO

% Let's just make a random matrix first
rand_matrix = randi([10, 50], 8)

% Let's save and load some files!
save sampdata.dat rand_matrix -ascii
load sampdata.dat
disp sampdata
type sampdata.dat

% We can save variables in a file as well!
save params % Leaving no arguments saves all variables you have on hand
load params
who % Display it on the screen
a = 123
save -append params a % This appends to the normal variable

3.20 Eval

If you know Python you should know what this does already.

Eval executes strings as code!

toExecute = spritnf('total = %d + %d', 5, 4)
eval(toExecute) % Executes it as:
% total = 5 + 4

3.21 Pausing

You can pause in MATLAB too! Think of it like Arduino delay() or Python time.sleep()

pause(5) % Pause for 5 seconds

pause off % Disable pause
pause on % Enable pause

4. Functional and OOP MATLAB

4.1 Functions

Functions have to come at the end of your file!

Local and global variable rules still apply! Local variables defined in functions don't change outside of the function! Just take note!

% Function to calculate volume
% The return is defined by the name preceding the =
% The name of the function is the name following the =

% In this case, the return is 'vol' and the function name is 'cylinderVol'
function vol = cylinderVol(radius, height)
    vol = pi radius^2 * height
end

% Let's try another one! This time a function with no arguments
function randNum = getRandomNum
    randNum = randi([1, 100])
end

% Return more than one value
[coneV, cylVol] = getVols(10, 20) % I'll call the function here, and define it below

function [coneVol, cylinVol] = getVols(radius, height)
    cylinVol = pi * radius^2 * height
    coneVol = 1/3 * cylinVol
end

% Variable Number of Arguments
function sum = getSum(varargin)
    sum = 0;
    for k = 1:length(varargin)
        sum = sum + varargin{k}(1);
    end
end

% Return variable number of outputs
function [varargout] = getNumbers(howMany)
    for k = 1:howMany
        varargout{1}(k) = k;
    end
end

4.2 Anonymous Functions

No named functions! Think lambda in python

cubeVol = @ (l, w, h) l * w * h; % (input) output

a = cubeVol(2, 2, 2) % Gives you 8! Correct!

Pass Function to another Function

Think decorators!

Source: https://www.youtube.com/watch?v=NSSTkkKRabI

mult3 = @ (x) x * 3;
sol = doMath(mult3, 4)

function sol = doMath(func, num)
    sol = func(num);
end

Returning Functions

Source: https://www.youtube.com/watch?v=NSSTkkKRabI

mult4 = doMath2(4);
sol2 = mult4(5)

function func = doMath2(num)
    func = @(x) x * num;
end

4.3 Recursive Functions

They call themselves!

function val = factorial(num)
if num == 1
    val = 1;
else
    val = num * factorial(num - 1);
end
end

4.4 Classes

Static members are shared amongst all members of a class

classdef Shape
    properties % Variables!!!
        height
        width
    end

    methods(Static)
        function out = setGetNumShapes(data)
            % Persistent values are shared by all objects also
            persistent Var;
            if isempty(Var)
                Var = 0;
            end
            if nargin % Number of input arguments
                Var = Var + data
            end
            out = Var;
        end
    end

    methods
        % Define a constructor
        function obj = Shape(height, width)
            obj.height = height
            obj.width = width
            obj.setGetNumShapes(1)
        end
        % Overloaded disp function
        % If you don't know what overloading is, check my C++ tutorial. It basically overwrites the functionality of a pre-existing function if the argument number matches
        function disp(obj)
            fprintf('Height : %.2f / Width : %.2f\n', obj.height, obj.width)
        end
        function area = getArea(obj)
            area = obj.height * obj.width;
        end
        % Overload Greater Than function
        function tf = gt(obja, objb)
            tf = obja.getArea > objb.getArea
        end
    end
end

Let's try using it!

a1 = Shape(10, 20)
disp(a1)
Shape.setGetNumShapes
a1.getArea

a2 = Shape(5, 10)
disp(a2)
Shape.setGetNumShapes

a1 > a2

4.5 Class Inheritance

classdef Trapezoid < Shape % Trapezoid inherits from Shape

    properties
        width2
    end

    methods
        function obj = Trapezoid(height, width, width2)
            obj@Shape(height,width) % The @ sign means you're taking it from the parent
            % In this case we're using Shape's constructor!
            obj.width2 = width2
        end
        function disp(obj)
            fprint('Height : %.2f / Width : %.2f / Width2 : %.2f', obj.height, obj.width, obj.width2);
        end
        function area = getArea(obj)
            area = (obj.height/2) * (obj.width + obj.width2);
        end
    end
end

Let's try it out!

a3 = Trapezoid(10, 4, 6)
disp(a3)
a3.getArea

5. Plotting

5.1 Plotting in MATLAB

Source: https://www.youtube.com/watch?v=NSSTkkKRabI

help plot for help!

xVals = 1:5
yVals = [2 4 8 5 9]
yVals2 = [1 5 7 6 8]

figure(1)
plot(xVals, yVals, 'g+', 'LineWidth', 2)
hold on % Draw over what was plotted, keep plot settings
plot(xVals, yVals2, 'k*')
legend('yVals', 'yVals2')

grid on % Turn grid on

xlabel('Days')
ylabel('Money')
title('Money Made Today')
figure(2)
bar(xVals, yVals, 'r')

% Colors : blue(b), black(k), cyan(c), green(g),
% magenta(m), red(r), yellow(y), white(y)
% Plot Symbols : . o x + * s d v ^ < > p h
% Line Types : -, :, -., - -

% Set font weights and the like
% gca is the axis object, gcf is the figure object
set(gca, 'FontWeight', 'bold', 'FontSize', 20, 'color', 'white');
set(gcf, 'color', 'white')

clf % Delete all figures

Example Sinusoid with Time

y = A.*cos(2*pi .* t/T - 2*pi .* x/lambda + phi0);

5.2 3D Plotting in MATLAB

3D Plots and Meshgrids

plot3() % Use this instead of plot2!

% Example
t = 0: pi/50 : 10*pi;
plot3(sin(t), cos(t), t)

% Meshgrids
meshgrid()

Surfaces

% Plot surfaces
cylinder()
sphere()

surf() % Plot a surface
isosurface() % For when plotting normal surfaces are too hard
contour() % Plot a contour map instead

Vector Fields

quiver() % 2D
quiver3() % 3D

colorbar % Add a colorbar!

6. Intermediate and Advanced Math

6.1 Vector Calculus

gradient()
divergence()
curl()
del2() % Discrete laplacian

                            .     .
                         .  |\-^-/|  .    
                        /| } O.=.O { |\

​

Loops / Conditionals

for

for i=start:counter:finish
	statement1
	statement2
	...
end

while

while condition
	statement1
	statement2
	...
end

if else

if condition1
	statement1
elseif condition2
	statement2
else
	statement3
end

Footer

GUI

Create Figure

h.fig =  figure('Name', 'titel_der_figur', ...
        'NumberTitle', 'off', ...
        'position', [left bottom width height], ...
        'Resize', 'off', ...
        'Menubar', 'none');

static text

h.text = uicontrol('Style', 'text',...
        'Parent', h.panelControl, ...
        'FontSize', 14, ...
        'String', 'CHOOSE ALGORITHM',...
        'Units', 'normalized', ...
        'Position', [0 0 1 1],...
        'Callback', @setmap);   

popup menu

h.popupmenu = uicontrol('Style', 'popup',...
        'Parent', h.panelControl, ...
        'String', {'Entry1','Entry2','Entry3'},...
        'Units', 'normalized', ...
        'Position', [left bottom width height],...
        'Callback', @setmap);   

plot inside a panel

h = figure;
hp = uipanel('Title','Main Panel','FontSize',12,...
             'BackgroundColor','white',...
             'Position',[.25 .1 .67 .67]);

sp1 = subplot(2, 2, 1, 'Parent', hp);
plot(1:10);
sp4 = subplot(2, 2, 4, 'Parent', hp);
surf(peaks);

Bash

random by max number of case

$ echo ${RANDOM:0:3}

substitution

• remove dirname

f="./4-Attya-anatomie/expose.pdf"
echo ${f##*/}

expose.pdf

• extension

file=ra.pdf
echo "${file:0:-4}"

ra

$ f="/etc/resolv.conf"
$ echo "${f#/etc/}"

resolv.conf

• not determiner fisrt match

$ f="/etc/resolv.conf"
$ echo "${f#*/}"

resolv.conf

interpreted var : eval it

hello=2020
var="hello"
echo ${!var}
# 2020

format string like a table

• select words
• add spaces
• trim spaces: by accept only 14 char

sed 's/\(\(\w\|+\| \)\{14\}\) */\1'

loop in array

declare -a arr=(
      "already"
      "amssymb"
      "array"
)

for item in "${arr[@]}";do
  #...
done

pass array to function

f() {
    declare -a argAry1=("${!1}")
    echo "${argAry1[@]}"
}

arr1=(
    "a"
    "b"
)
f arr1[@] arg2 arg3

readarray -t fr < fr.txt

array_of_lines=("${(@f)$(my_command)}")

use args

while getopts "a:b:r:c:C:T:Kk:l:i:I:s:o:p:v:h" opt; do
    case $opt in
        a) BASE_ARCH="$OPTARG";;
        b) BASE_SYSTEM_PKG="$OPTARG";;
        r) XBPS_REPOSITORY="--repository=$OPTARG $XBPS_REPOSITORY";;
        c) XBPS_CACHEDIR="$OPTARG";;
        K) readonly KEEP_BUILDDIR=1;;
        k) KEYMAP="$OPTARG";;
        l) LOCALE="$OPTARG";;
        i) INITRAMFS_COMPRESSION="$OPTARG";;
        I) INCLUDE_DIRECTORY="$OPTARG";;
        s) SQUASHFS_COMPRESSION="$OPTARG";;
        o) OUTPUT_FILE="$OPTARG";;
        p) PACKAGE_LIST="$OPTARG";;
        C) BOOT_CMDLINE="$OPTARG";;
        T) BOOT_TITLE="$OPTARG";;
        v) LINUX_VERSION="$OPTARG";;
        h) usage;;
	*) usage;;
    esac
done

find files that's binaty

find . -type f ! -size 0 -exec grep -IL . "{}" \;

Some color for bash

# Color
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m' # No Color

function red {
    printf "${RED}$@${NC}\n"
}

function green {
    printf "${GREEN}$@${NC}\n"
}

function yellow {
    printf "${YELLOW}$@${NC}\n"
}

read file by while

while IFS= read -r line; do
    echo "Text read from file: $line"
done < my_filename.txt

Hide some error

add this to your script file.sh

# shellcheck disable=SC1117,SC2001

switch case in c

  switch (a) {
    case 100:
      // Code
      break;
    case 200:
      // Code
      break;
    default:
      // Code
      break;
  } 

compare two strings

if (strcmp(s1,s2)==0){
    //true
}

multi string concate

  strcat(strcat(s1,s2),s3);
  strcat(strcat(strcat(s1,s2),s3),s4);
  strcat(strcat(strcat(strcat(s1,s2),s3),s4),s5);

#include <criterion/criterion.h>
// https://github.com/Snaipe/Criterion/blob/bleeding/samples/asserts.c

str1 == str2: eq

// need for str,...
#include <criterion/new/assert.h>

Test(..., ...) {
    cr_assert(eq(str, "hello", "hello"));
}

function return 1 or bool

Test(..., ...) {
    cr_assert(true);
}

str1 == "":

Test(..., ...) {
    char s1="";
    cr_assert(zero(str, s1));
    cr_assert(not (zero(str, s1)));
}

init/finish

void setup(void)
{
    puts("Runs before the test");
}

void teardown(void)
{
    puts("Runs after the test");
}

// must add this args at the end
Test(..., ..., .init = setup, .fini = teardown){
}

read line by line

  while (!feof (fp)) {
    if (fgets(line, sizeof (line), fp)) {
      printf("next line= %s\n", line);
    }
  }

read to char or first line

   fscanf(fp, "%[^\n]", line);
   printf("Data from the file:\n%s", line);

• void readFirstLine(char *file,char *line) in ayoub/file

• Give a error whenever a function is used before being declared

$ gcc -Werror-implicit-function-declaration

• Give a error whenever a function is used without prototypes

$ gcc -Wstrict-prototypes -Wmissing-prototypes

• option makes using -S to inspect the assembly output much, much nicer.

$ gcc -masm=intel

• esstentiel

$ gcc -Wall -Wextra -Wfloat-equal -Os -ggdb

• stops the compilation if has and big warrning

$ gcc -Werror

• small executable

$ gcc -s

• cheack printf and scanf

$ gcc -Wformat=2

• gcc version

$ gcc -std=c99

GDB

print

• string

p s

• first 3 element in any arrays

p s@3

go back : gdb prev

target record-full
run
reverse-next
reverse-step

change var value from 3 to 7

main(){
  int i=7
}

set variable i = 7

change string value

int main(){
  char[] person = "Bob";
}

set main::person = "Sam"

gdb config

cat ~/.gdbinit

gdb source view

gdb -tui

gdb in vim

let g:termdebug_wide = 10 | packadd termdebug | Termdebug

MAKE

look some CFLAGS

clang -c a.c # it's create a.o
clang a.o f.o -o a
./a

• use cflags without quote: ' or "

CFLAGS=-Wno-deprecated-declarations -Wno-format-security -lm `pkg-config --cflags --libs gtk+-3.0` -export-dynamic
LDFLAGS=`pkg-config --libs gtk+-3.0`

• use all: app not all app:
• help clangd and ccls

bear -- make > compile_commands.json

my function in mylib

• read first line from *file and return fist &line

void readFirstLine(char *file, char *line);

• read nth line from *file and return the nth &line

void readOneLine(char *file, char *s, int N);

• read int from *file and return x

int fgetint(char *file);

• read *file and return as &string

void fgetString(char *file, char *s);

• run shell coomad and return output as &string

void stdoutOneline(char *s_in, char *s_out);

array of function Pointers

like switch cases to run the functions:

• function:

 int sum(int a,int b);
 int sub(int a,int b);

• main:

int (*option[2])(int,int);
option[1]=sum;
option[2]=sub;

printf("%d",option[1](1,2)); // sum(1,2) --> 3

how to make so/share library

$ gcc -o libx.so -fpic -shared libx.c # libx.c -> libx.so
$ ln -s x.h /usr/include/ayoub/x.h
$ ln -s libx.so /lib                  #
$ gcc -c main.c -o main.o             # main.c -> main.o
$ gcc -o main main.o -lx              # main.o +  mylib

how to use it in Makefile

just add -lx to cflags

Check for lib

to view the function that already define or undefine(need lib.so)

$ nm a.out

how to view shared lib from app

$ ldd a.aout

how to sleep in c: waiting

  #include <unistd.h>
  sleep(5);

STRING

pass char[][] to function

• stackoverflow

• check no duplocate from my github

• function to read char[][] 2D

void readMatrix( char *matrix[][cols]) {
    matrix[i][j] = "aaa";
}

char *mat[rows][cols];
readMatrix(mat);

• with maloc and pointer

void readMatrix(char**** matrix){
    *matrix = malloc(rowNum*sizeof(char**));
    for(int i=0;i<rowNum;i++){
        *(*matrix+i) = malloc(columnNum*sizeof(char*));
    }

    *(*(*matrix+i)+j) = malloc(MAX_WORD_SIZE*sizeof(char));
    scanf("%s",*(*(*matrix+i)+j));
}
char*** inputMatrix;
readMatrix(&inputMatrix);
printf("%s ",*(*(inputMatrix+i)+j));

Read string with white space from file with fscanf

    char s[40];
    fscanf (fp, "%d,%f,%[a-zA-Z ]\n", &i, &x, s);

how to convert str to int

• ust sprintf()

sprintf(s, "%d", x);
printf("%s\n",s);

pass arry of sruct

• my answer in stackoverflow
• struct:

typedef struct top {
    int tot;
    char s[100];
} top;  

• main:

int main() {
    top **t_array = malloc(100 * sizeof(top *));
    t_array[0] = malloc(sizeof(top));
    t_array[0]->tot = 10;
    f1(t_array);
}

• function:

void f1(top **t_array) {
    t_array[0] = malloc(sizeof(top));
    t_array[0]->tot = 11;
}

without array

typedef struct top {
    int tot;
} top;

• main

top *array1 = malloc(MAX * sizeof(top));
array1->tot=11;

swap (permutaion) tow struct

top* tmp = t_trie[j];
t_trie[j] = t_trie[i];
t_trie[i] = tmp;

Get time

struct tm {
   int tm_sec;         /* seconds,  range 0 to 59          */
   int tm_min;         /* minutes, range 0 to 59           */
   int tm_hour;        /* hours, range 0 to 23             */
   int tm_mday;        /* day of the month, range 1 to 31  */
   int tm_mon;         /* month, range 0 to 11             */
   int tm_year;        /* The number of years since 1900   */
   int tm_wday;        /* day of the week, range 0 to 6    */
   int tm_yday;        /* day in the year, range 0 to 365  */
   int tm_isdst;       /* daylight saving time             */
};

Rust

• C like
• Error
• Struct

Notion

• mut , all variables are const, to make it modifiable added the mut
• Result of a .method_name() is an enum.
• We call each possible state of Result a variant.
• Result's variants for .read_line() are Ok and Err.
• The blocks of code after if: called arms {}
• let mut s="jjj" not allowed,
• let mut s=String::from("jjj") allowed using the heap mémoire
• let s2 = s1: s1 move to s2, then s1 will be droped

re-use Var: shadows

#![allow(unused)]
fn main() {
let x=10;
let x="ll";
}

• mut not allowing the shadows

#![allow(unused)]
fn main() {
let mut x=10
x="ll";

}

variables

#![allow(unused)]
fn main() {
let x : i32= 4; // u32,u8..
let x : i32= 4_000; // 4_000 == 4000

let y: f32 = 3.0; // defualt is f64
let floored = 2 / 3; // Results in 0

let t: bool = false;

let heart_eyed_cat: char = '😻';// 'z' ...should use single for char
}

Tuple

#![allow(unused)]
fn main() {
let tup:(i32, f64, u8) = (500, 6.4, 1.5);
let (x, y, z) = tup;
println!("The value of z is: {z} or {} or {tup.2} or {}",tup.2); // {tup.2} -> not allowed
}

Arr

Unlike a tuple, every element of an array must have the same type. Unlike arrays in some other languages, arrays in Rust have a fixed length.

#![allow(unused)]
fn main() {
let a = [1, 2, 3, 4, 5];
let first = a[0];
}

What Is Ownership?

Memory is managed through a system of ownership with a set of rules that the compiler checks. If any of the rules are violated, the program won’t compile. None of the features of ownership will slow down your program while it’s running.

• Ownership Rules
  • Each value in Rust has an owner.
  • There can only be one owner at a time.
  • When the owner goes out of scope, the value will be dropped.
• the error double free error is solved by shallow copy

shallow copy: not drop the heap data of var if this data shared between another var

• deep copy, s1 and s2 will be separated

#![allow(unused)]
fn main() {
let s1 = String::from("hello");
let s2 = s1.clone();
}

• types that used head memory used move and other used copy function

#![allow(unused)]
fn main() {
    let s = String::from("hello");
    takes_ownership(s);
    s:String("new"); // not allowed because moved from this scope
}

C like

import

#![allow(unused)]
fn main() {
use std::io;
}

c scanf in rust

#![allow(unused)]
fn main() {
io::stdin()
    .read_line(&mut guess)
    .expect("Failed to read line");
}

c #define in rust

#![allow(unused)]
fn main() {
// #define ABC 40 * 60 * 3
const ABC: u32 = 60 * 60 * 3;
}

c rand() in rust

#![allow(unused)]
fn main() {
use rand::Rng;
let secret_number = rand::thread_rng().gen_range(1..=100);
}

compare value to another value

#![allow(unused)]
fn main() {
use std::cmp::Ordering;
match guess.cmp(&secret_number) {
    Ordering::Less => println!("Too small!"),
    Ordering::Greater => println!("Too big!"),
    Ordering::Equal => println!("You win!"),
}
}

cast

#![allow(unused)]
fn main() {
let guess: u32 = "42".parse().expect("Not a number!");
}

if

#![allow(unused)]
fn main() {
if number < 5 {
    println!("condition was true");
} else {
    println!("condition was false");
}
}

#![allow(unused)]
fn main() {
let number = if condition { 5 } else { 6 };
}

loop

• simple break

#![allow(unused)]
fn main() {
let result = loop {
    counter += 1;

    if counter == 10 {
        break counter * 2;
    }
};
}

• break outside and inside

fn main() {
    let mut count = 0;
    'counting_up: loop {
        println!("count = {count}");
        let mut remaining = 10;

        loop {
            println!("remaining = {remaining}");
            if remaining == 9 {
                break;
            }
            if count == 2 {
                break 'counting_up;
            }
            remaining -= 1;
        }

        count += 1;
    }
    println!("End count = {count}");
}

while

#![allow(unused)]
fn main() {
while number != 0 {}
}

for

#![allow(unused)]
fn main() {
let a = [10, 20, 30, 40, 50];

for element in a {}
for number in (1..4).rev() {}
}

ERROR

• double free error :

#![allow(unused)]
fn main() {
let s1 = String::from("hello");
let s2 = s1;
}

This is a problem: when s2 and s1 go out of scope, they will both try to free the same memory. This is known as a double free error and is one of the memory safety bugs we mentioned previously. Freeing memory twice can lead to memory corruption, which can potentially lead to security vulnerabilities.

Struct

fn main() {
    let mut user1 = User {
        email: String::from("someone@example.com"),
        username: String::from("someusername123"),
        active: true,
        sign_in_count: 1,
    };
    user1.email = String::from("anotheremail@example.com");
}

return a struct

struct User {
    //...
}

fn build_user() -> User {
    User {
        //...
    }
}

fn main() {
    let user1 = build_user(...);
}

Merge tow struct

fn main() {
    let user1 = User {
         // ....
        };

    let user2 = User {
        email: String::from("another@example.com"),
        ..user1
    };
}

struct as tuple

struct Color(i32, i32, i32);
struct Point(i32, i32, i32);

fn main() {
    let black = Color(0, 0, 0);
    let origin = Point(0, 0, 0);
}

Ownership of Struct Data

we used the owned String type rather than the &str string slice type. for that data to be valid for as long as the entire struct is valid.

to store references to data owned by something else, it's require to use the lifetimes, to ensure the data referenced by a struct is valid for as long as the struct is.

Methode with struct

struct Rectangle {
   width: u32,
   height: u32,
}

// snip ...
impl Rectangle {
    fn area(&self) -> u32 {
        self.width * self.height
    }
    fn can_hold(&self, other: &Rectangle) -> bool {
        self.width > other.width && self.height > other.height
    }
}

fn main() {
   let rect1 = Rectangle {
       width: 30,
       height: 50,
   };
  let rect2 = Rectangle {
      width: 10,
      height: 40,
  };

   println!(
       "The area of the rectangle is {} square pixels.",
       rect1.area()
   );
   println!("Can rect1 hold rect2? {}", rect1.can_hold(&rect2));
}

enum

enum IpAddrKind {
    V4,
    V6,
}

fn main() {
    let four = IpAddrKind::V4;
    let six = IpAddrKind::V6;

    route(IpAddrKind::V4);
    route(IpAddrKind::V6);
}

fn route(ip_kind: IpAddrKind) {}

Enum with struct

fn main() {
    enum IpAddrKind {
        V4,
        V6,
    }

    struct IpAddr {
        kind: IpAddrKind,
        address: String,
    }

    let home = IpAddr {
        kind: IpAddrKind::V4,
        address: String::from("127.0.0.1"),
    };

    let loopback = IpAddr {
        kind: IpAddrKind::V6,
        address: String::from("::1"),
    };
}

Enum as args as tuple

fn main() {
    enum IpAddr {
        V4(u8, u8, u8, u8),
        V6(String),
    }

    let home     = IpAddr::V4(127, 0, 0, 1);
    let loopback = IpAddr::V6(String::from("::1"));
}

Example

enum Coin {
    Penny,
    Nickel,
    Dime,
    Quarter,
}

fn value_in_cents(coin: Coin) -> u8 {
    match coin {
        Coin::Penny => 1,
        Coin::Nickel => 5,
        Coin::Dime => 10,
        Coin::Quarter => 25,
    }
}

fn main() {
    value_in_cents(Coin::Quarter(UsState::Alaska));
}

• how to use value_in_cents:
  • how to call it
  • how to receive return value, is there always the same type u8,int...
  • tow to send and enum or one variant from enum

with if, the expression needs to return a Boolean value, but here, it can return any type. The type of coin in this example is the Coin enum

#[derive(Debug)] // so we can inspect the state in a minute
enum UsState {
    Alabama,
    Alaska,
    // --snip--
}

enum Coin {
    Penny,
    Nickel,
    Dime,
    Quarter(UsState),
}

fn main() {}

Match

#[derive(Debug)]
enum UsState {
    Alabama,
    Alaska,
    // --snip--
}

enum Coin {
    Penny,
    Nickel,
    Dime,
    Quarter(UsState),
}

fn value_in_cents(coin: Coin) -> u8 {
    match coin {
        Coin::Penny => 1,
        Coin::Nickel => 5,
        Coin::Dime => 10,
        Coin::Quarter(state) => {
            println!("State quarter from {:?}!", state);
            25
        }
    }
}

fn main() {
    value_in_cents(Coin::Quarter(UsState::Alaska));
}

Option

fn main() {
    fn plus_one(x: Option<i32>) -> Option<i32> {
        match x {
            None => None,
            Some(i) => Some(i + 1),
        }
    }

    let five = Some(5);
    let six = plus_one(five);
    let none = plus_one(None);
}

Catch All

fn main() {
    let dice_roll = 9;
    match dice_roll {
        3 => add_fancy_hat(),
        7 => remove_fancy_hat(),
        other => move_player(other),
        _ => reroll(),
        _ => (),

    }

    fn add_fancy_hat() {}
    fn remove_fancy_hat() {}
    fn move_player(num_spaces: u8) {}
}

If let

fn main() {
    let config_max = Some(3u8);

    match config_max {
        Some(max) => println!("The maximum is configured to be {}", max),
        _ => (),
    }
    // equivalent
    if let Some(max) = config_max {
        println!("The maximum is configured to be {}", max);
    }
}

#[derive(Debug)]
enum UsState {
   Alabama,
   Alaska,
   // --snip--
}

enum Coin {
   Penny,
   Nickel,
   Dime,
   Quarter(UsState),
}

fn main() {
   let coin = Coin::Penny;
    let mut count = 0;
    match coin {
        Coin::Quarter(state) => println!("State quarter from {:?}!", state),
        _ => count += 1,
    }
    // equivalent
    if let Coin::Quarter(state) = coin {
        println!("State quarter from {:?}!", state);
    } else {
        count += 1;
    }
}

how to substitute assets in pebstect.yaml

  g/^....assets:/s/....assets:/  assets:\r    - assets\/*

flutter run -d linux --pid-file /tmp/flutter.pid

• if you want to pass function delete from class A to class B

  • don't use : final Function? delete;
  • but use : final VoidCallback? delete;

• if you get the error null:
  use String foo? ; foo!;

• if you want to use wait B.fun(await ...) in class A:

  • you must add Future<void/int> fun(){await ...} in class B
  • than use the await B.fun.. in class A
  • but don't forget to add async in class A..

• if you want to use the hot reload by plugin flutter-tools

  • use the script to kill the pid of app that running

List of models

List<Quote> list=[Quote(text: 'll', author: '') ];

map listview

main:

class MyApp....{}
class _MyAppState extends State<MyApp> {
  late final Quote quote;
  List<Quote> quotes = [
    Quote(text: 'fsm mks', author: 'ayoub'),
    Quote(text: 'fsm rabat', author: 'aly'),
    Quote(text: 'fsm mauritanya', author: 'rachid'),
  ];
  @override
  Widget build(BuildContext context) {
    return Column(
      children: quotes.map((quote) => Text('${quote.text}- ${quote.author}')).toList(),
    );

to

• main:

class MyApp....{}
class _MyAppState extends State<MyApp> {
  late final Quote quote;
  List<Quote> quotes = [
    Quote(text: 'fsf mks', author: 'ayoub'),
    Quote(text: 'fsm rabat', author: 'aly'),
    Quote(text: 'fsm mauritanya', author: 'rachid'),
  ];
  @override
  Widget build(BuildContext context) {
    return Column( 
        children: quotes .map((quote) => Mycard(quote:quote)) .toList(),
    );

• class:

//import...

class Mycard extends StatelessWidget {
    final Quote quote;
    const Mycard({Key? key, required this.quote}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Padding(
      child: Card(child: Text('${quote.text} -- ${quote.author}')),
    );
  }
}

use keyword require:

class Quote {
  String author = "";
  String text = "";
  Quote({required this.author, required this.text});
}

call:

Quote(text: 'll', author: '')

list of models:

    List<Quote> list=[Quote(text: 'll', author: '') ];

rooting

• use routes:{key:val,...}

• import layout

  import 'package:app9/pages/choose_location.dart';
  import 'package:app9/pages/home.dart';
  import 'package:app9/pages/looding.dart';
  import 'package:flutter/material.dart';
  
  void main() => runApp(MaterialApp(
        initialRoute:'/',
        routes: {
          '/': (context) => Loading(),
          '/home': (context) => Home(),
        },
      ));
  

• don't use duplique roationg, like:

  runApp(
      Home(),
      routes:{'/home'}
  )
  

alignment: left/start/right ..

child: Column(...,crossAxisAlignment: CrossAxisAlignment.start)

image

flutter:
  assets:
    - assets/images/

child: Image(
  height: 100,
  image: AssetImage('assets/images/img1.png'),
),

Text

// const int grey50 = 0xFFFAFAFA;
const Text(
  'Name',
  style: TextStyle(
    fontSize: 14,
    color: Color(grey400),
  ),
),

Separateur Divider

const SizedBox(height: 20),

Column

• column inside scafold

return Scaffold(
  appBar: AppBar(
    title: const Text('Material App Bar'),
  ),
  body: Column(
    children: <Widget>[
      const Center(
        child: Image(),
        ),
    ],
  ),
);

• scafold->padding...->column

return Scaffold(
  body: Padding(
    child: Column(
      children: <Widget>[
        const Center(
          child: Image(),
        ),
      ],
    ),
  ),
);

Icon

children: [Icon(Icons.tv)],

children: [
ElevatedButton.icon(
    onPressed: (){},
    icon: const Icon(Icons.delete),
    label: const Text('delete quote'),
)
],

button

VOID LUNUX

xbps-install -Sy pkg-config gtk+3-devel clang

pubspec.yaml

dependencies:
  sprintf:

main.dart

import 'package:sprintf/sprintf.dart';

  String numbers = sprintf('Your score is %2.2f points.', [score]);
  String sentence = sprintf('Hello %s, You have %d years old.', [name, years]);

string.format

string.format("%s %q", "Hello", "Lua user!")   -- string and quoted string

Hello "Lua user!"

string.sub("taaaaaaest.lua",1,-5)

taaaaaaest

gmatch

for word in string.gmatch("Hello Lua user", "%a+") do
    print(word)
end

Hello
Lua
user

• match pattern in lua

%d matches a digit
%u matches an uppercase letter
%a: letter %s: whitespace

string.match("%*^", '%%%*%^')

%*^

JavaScript

Install latex on voidlinux

should use `^texlive-20210325_4' is you want to use binary

xbps-install -Sy texlive-20210325_4

Bash Var

export TEXMFHOME=~/.texmf
export PERL5LIB="/usr/share/texmf-dist/tlpkg:<span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.08125em;">H</span><span class="mord mathnormal" style="margin-right:0.05764em;">OME</span><span class="mord">/</span><span class="mord mathnormal">tlp</span><span class="mord mathnormal" style="margin-right:0.03148em;">k</span><span class="mord mathnormal" style="margin-right:0.03588em;">g</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">:</span></span></span></span>HOME/.cpan/build:PERL5LIB"

Stow

latex in dotfile continent TLConfig.pm ...

stow latex

link

this version not continent tlpkg/installer/tlconfig.guess

sudo chown {USER}:users /
ln -sf /usr/share/texmf-dist/tlpkg /tlpkg

choose old repo for old latex-2021

tlmgr option repository https://ftp.tu-chemnitz.de/pub/tug/historic/systems/texlive/2021/tlnet-final
tlmgr update

successive

\newcommand{\myitem}{\item[$\blacksquare$]}

\begin{frame}{Historique}
    \begin{itemize}[<+-|alert@+>]
        \myitem 1950
        \myitem 1970
    \end{itemize}

    \only<1>{
    \begin{exampleblock}{XXXX}
        ...
    \end{exampleblock}
    }

    \only<2>{
    \begin{exampleblock} {YYY}
        ..
    \end{exampleblock}
    }

    \vspace{80mm}
\end{frame}

intalation : latex to text

https://github.com/pkubowicz/opendetex
/projects/c/opendetex

online converter:

https://www.vertopal.com/en/convert/pdf-to-tex

fix luatex/xetex/pdftex

\documentclass[a4paper,11pt,twoside]{report} %twoside pour une présentation différente des pages paires/impaires, car dans la classe report, l'option oneside est par défaut
\usepackage{iftex}
\ifPDFTeX
  \usepackage[mathletters]{ucs}
  \usepackage[utf8x]{inputenc}
   % \usepackage[utf8]{inputenc}
   \usepackage[T1]{fontenc}
   \usepackage{lmodern}
\else
   \ifXeTeX
     % \usepackage[mathletters]{ucs}
     % \usepackage[utf8x]{inputenc}
     \usepackage{fontspec}
   \else 
     \usepackage{luatextra}
   \fi
   \defaultfontfeatures{Ligatures=TeX}
\fi

zref-abspage.sty

$ set zref set zref zref-abspage.sty zref-abspos.sty zref-base.sty zref-counter.sty zref-dotfill.sty zref-env.sty zref-hyperref.sty zref-lastpage.sty zref-marks.sty zref-nextpage.sty zref-pageattr.sty zref-pagelayout.sty zref-perpage.sty zref-runs.sty zref-savepos.sty zref-thepage.sty zref-titleref.sty zref-totpages.sty zref-user.sty zref-xr.sty zref.sty
$ for file in $zref;wget 'https://raw.githubusercontent.com/manuels/texlive.js/master/texlive/texmf-dist/tex/latex/oberdiek/'$file;end
$ output to $prefix/texmf/tex/latex not $prefix/texmf-dist/tex/latex
$ ln -s /texmf-dist/tex/latex/oberdiek ~/texmf/tex/latex

declare

must start with include then declar command

fix tlmgr usermode+ pacage is 2020 but install 2021

find a userpackage

$ tlmgr search --global --file beamerthemeShadow

create manually pkg in /texmf-dist/tex/latex

$ mkdir /texmf-dist/tex/latex/pkg1
$ texhash /texmf-dist

update 4:

- tlmgr repo is old: i can go back to the old reposotory by change the`tlmgr reposotory`
```bash
$ tlmgr option repository https://ftp.tu-chemnitz.de/pub/tug/historic/systems/texlive/2021/tlnet-fina
```

update 3:

• latex as bin

  $ xbps-install -Sy i texlive-20210325_2
  

• latex mk

  • already include

• tlmgr already include

  $ ln -s $HOME/scripts/latex/tlmgr /sbin
  

• TeXLive/TLPDB.pm

  • already include dans texlive-core-2021.58710_1

  $ wget https://raw.githubusercontent.com/TeX-Live/installer/master/tlpkg/TeXLive/TLUtils.pm^C
  
  

• latexpkg: auto install missing pkg

  $ ln -s $HOME/scripts/latex/latexpkg /sbin
  

• verification de reposotory: not sure

  $ # tlmgr init-usertree
  

• define tlpkg

$ ln -s /usr/share/texmf-dist/tlpkg /

• luatex & bibtex

$ xbps-install -Sy texlive-LuaTeX texlive-BibTeX

UPDATE 2:

• init tlmgr

$ tlmgr init-usertree

• active usermode for root in voidlinux
  • by alias:

  $ alias tlmgr='/usr/share/texmf-dist/scripts/texlive/tlmgr.pl --usermode'
  

  • or sumlink

  $ cat /sbin/tmlgr
  
  
  #!/bin/sh
  exec /usr/share/texmf-dist/scripts/texlive/tlmgr.pl --usermode "$@"
  

• geus

UPDATE:

xbps binary

$ xbps-install -Sy texlive-20210325_2

localte module

if tmlgr can't locate TeXlive::.... - link path that reaserch by tlmgr ln -s /usr/share/texmf-dist /texmf-dist - download module manuly to /texmf-dist/scripts/texlive/TeXLive/... - use alias tl='$(which tlmgr) --usermode'

OLD:

$ xbps-install -Sy texlive2021-bin-2021_1

fix version 2021

$ vim `which tlmgr` or 
$ vim TEXMFDIST/scripts/texlive/tlmgr.pl

and replace $Master = "$Master/../.."; with $Master = "${Master}/../../..";

• download la latexmk and make symbloic link

$ ln -s /opt/texlive2021-installer/texmf-dist/scripts/latexmk/latexmk.pl /usr/bin/latexmk 

• alias use script to create tlmgr

alias tlmgr="/opt/texlive2021-installer/texmf-dist/scripts/texlive/tlmgr.pl --usermode"

install cpan for latexindent

$ export PERL5LIB="$HOME/.cpan/build:$PERL5LIB"
$ cpan Log::Log4perl File::HomeDir YAML::Tiny Unicode::GCString 

• to remove perl/cpan module:

$cpanm --uninstall YAML::Tiny module

• this module install at:

$ ls $HOME/perl5/lib/perl5

insert latex symbols by copy

view wiki/latex/fix.md

fix

make all command \bo declared after using

position of text

A---------B
1    2    3

for write text below A,

  \draw (A) node[below]{1} -- (B) ;

for write text below Midle of (A,B),

  \draw (A)                -- node[below]{2} (B) ;

for write text below B,

  \draw (A)                --                (B) node[below]{3};

variable

\pgfmathsetmacro{\angle}{60}

fuction like cos and sin

4*cos{\angle}, % not cos() with parentecise

loop

foreach \x in {0,...,5} {
  \draw (A) -- (0,\x)
};

vim

all buffer to splite vertical

:vert sb#

How to change default nvim directory

Fist time:

• change global var to new dirs:

XDG_CONFIG_HOME=~/.config  
XDG_DATA_HOME=~/.local  

XDG_CONFIG_HOME change to something like ~/test/
XDG_DATA_HOME change to something like ~/test/local
mkdir -p ~/test/{local,nvim} for create this tree of dirs:

  test
  ├── local
  └── nvim

~/test/nvim contian init.vim or init.lua ~/test/local` contian plug manager as Packer/Plug/Vundel

• Sync plugin for first time by run config file init.lua or init.vim

nvim ~/TEST-Cris/nvim/init.lua  

Seconde time:

• run ~/file.txt for example:

without alias

export XDG_CONFIG_HOME=~/test ;export XDG_DATA_HOME=~/test/local; nvim ~/file.txt 

with alias

with alias is fast , you should be add to .bashrc or ...

• alias vi

alias vi='export XDG_CONFIG_HOME=~/test ;export XDG_DATA_HOME=~/test/local; nvim' 

• run ~/file.txt for example:

vi ~/file.txt  

how write accenet alphabel fr french françias

é = '
è = `+!
ê = >
ë = :

ç = ,
œ = oe

• change color of dar1

$ diff lua/gruvebox/color.lua

 dark0_soft = hsl("#32302f"),
-dark1 = hsl("#3c3836"),
+dark1 = hsl("#272727"),
 dark2 = hsl("#504945"),

• change curlsorline cursor

$ diff lua/gruvebox/base.lua

 LineNr {fg = bg4, bg = number_column},
-CursorLineNr {fg = yellow, bg = bg1},
+CursorLineNr {fg = bg4, bg = number_column}

# xbps
$ xbps-install -Sy texlab nuspell clang shfmt shellcheck ccls StyLua

# pip
$ pip install autopep8 isort black yapf cmakelang

# npm
$ npm install -g bash-language-server prettier

luarcks need this app

xbps-install -Sy luarocks lua53-devel libnuspell-devel

make c file

:set makeprg=gcc\ -Wall\ -g\ %\ -o\ %<
:nnoremap ll :silent make<cr>:vs<cr>:term ./tp<cr>

wrap format tex

• set tw=70 : 70 char with line
• qg<motion>
• set formatoptions+=a : live wraping/formating

how use spell

set spelllang+=fr
setlocal spell
" <F5> :set local spell!<cr>

add new word to spell

• zg
• zG (temp dictionair)

add wrong word

• zw -zW (temp dic)

remove/undo word

• zug,zuw..