[PDF] Modification of a .pdf file

The direct edition of the text included in a .pdf file does appear to be straightforward. If the modification only concerns a few words (misprints,...), Inkscape may be used efficiently for that purpose.

Just open the .pdf file and modify the text where you want. This strategy generally works well but somefimes fails for a .pdf generated with MS Word.

[Matlab] fast reading of huge ASCII input files

The following code provides a rather fast way to deal with large ASCII data files containing groups of sub-data with different numbers of columns. For N=1E6 (leading to a ~2 M lines input file), the reading takes ~5 sec while the data reconstruction in matrix form lasts ~55 sec (on a 2012 laptop PC).

% Cleansing
clear all;
clc;

% Input Data
N=1E6;
x = 0:pi/N:pi;
y = [x; cos(x)];            %2 columns
xx= pi:pi/N:2*pi;
yy = [xx;cos(xx);sin(xx)];  %3 columns

% ASCII file writing
fprintf('* writing\n');
tic;
pfile = fopen('data.txt', 'w');
fprintf(pfile, '%12.8f %12.8f\n', y);
fprintf(pfile, '%12.8f %12.8f %12.8f\n', yy);
fclose(pfile);
toc;

% ASCII file reading
fprintf('\n* reading\n');
tic;
pfile=fopen('data.txt');
InputText=textscan(pfile,'%s','delimiter','\n');
fclose(pfile);
NN=length(InputText{1,1});
toc;

% Data matrix creation
fprintf('\n* matrix creation\n');
tic;
A=zeros(NN,3);
for i=1:NN
    line=InputText{1,1}{i,1};
    [str,count] = sscanf(line, '%s');
    if count == 2
        A(i,1:2)= sscanf(line, '%f %f');
    elseif count == 3
        A(i,1:3)= sscanf(line, '%f %f %f');
    end
end
toc;

[Abaqus] launching abaqus in command line

an example handling: the number of cpus involved, the memory allocation, the scratch directory :

abq610 job=MyJob cpus=12 memory=150GB scratch=/home/AbqScratch

Abaqus Finite Element Software:
http://www.simulia.com/

[Linux] permissions modification

When working on a server shared with other users, it seems suitable to restrict the access to personal files/directories.

The use of the command "chmod" can trigger rights for execution (+1), writing (+2) and reading (+4). Three perimeters are considered: the user (1st digit) , the usersgroup (2nd), everybody (3rd).

If one wants to restrict the access to his directory /home/MyRep for himself only, the command is then "chmod -R 700 /home/MyRep".

Ubuntu Linux distribution:
http://www.ubuntu.com/

[Abaqus] edition of viewport parameters

if one wants to modify the size/color/font/activation... of the written data displayed in the viewport, that's the place :

viewport/viewport annotation options (CAE 6.10-1)

Abaqus Finite Element Software:
http://www.simulia.com/

[Maths] Series convergence tests

Usually d'Alembert's ratio test is easier to perform than Cauchy's root test but it is less powerful (-> book Advanced mathematics for applications, Andrea Prosperetti, Cambridge University press).

On Amazon:
http://www.amazon.com/Advanced-Mathematics-Applications-Andrea-Prosperetti/dp/0521735874
On Google Books:
http://books.google.com/books?id=yQejXXN8zdoC

[LATEX] Re-installation

A far more tedious task than I remembered...

With a few blocking points:

* Installation of miktex:
configuration of the proxy : proxyweb.xxx.xx + port 3128 (not 8080 for me !!!)

* Compilation issue with an old miktex version :
error message:
! You are attempting to make a LaTeX format from a source file
! That is more than five years old.
solution:
edit \MiKTeX 2.8\tex\latex\base\latex.ltx
and change \ifnum\count@65 to \ifnum\count@165

* TexnicCenter tex=>pdf (with .eps images)
copy the basic tex=>.ps profile and add a postprocessor:
gs\gs9.04\bin\gswin64.exe
-sPAPERSIZE=a4 -dSAFER -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile="%bm.pdf" -c save pop -f "%bm.ps"

Miktex (Latex for Windows):
http://miktex.org/
Texniccenter (Latex environment for Windows):
http://www.texniccenter.org/
Latex softwares (including the all-in-one solution Protext for Windows)
http://tug.org/texcollection/