README

*** Please read this in its entirety before starting to write code. ***

== Directory and File Structure ==

I am anticipating that most new tools will be introduced by building 
their own sub-directories within wlrequirements. Several directories are 
used for specific purposes:

ErrorTree/  Script outputs that are terms in the error tree should go here.
            (2016-05-01: This is currently empty. When there are enough
            contributions to justify it, we will build postprocessing scripts
            that read this directory.)

InputData/  All sources of input data on the instrument design should go here
            (e.g. filter bandpasses, properties of the galaxy sample). All
            scripts reading text files from this directory should remove lines
            beginning with a hashtag (#). If your script requires information
            on the galaxy sample or instrument properties, please check first
            whether that information is here!

scr/        Used for scratch work or storage of intermediate results.

TeX/        Used for the paper (which serves as both the explanatory
            supplement and will be turned into a journal submission following
            SRR).

I'm also using references.txt for listings of references for code (in 
cases where they are previously published and/or we are not the 
authors).

== External Programs, Codes, and Libraries ==

The WL requirements package uses external tools that may be in different 
places on different machines.

You will need to create a "commands" file in this directory, each line 
of which is of the form:

class::/Users/christopherhirata/Desktop/CLASS_CMB/class_public-2.4.3/class

This tells the scripts where to find various external programs. The 
format is that the command name is first, followed by two colons (::), 
and then the path for that command (including the command itself).

The current list of commands required, and links for the packages, is 
noted below:

class [http://class-code.net]

Distributions of gcc and perl are required:

(*) gcc should be in your PATH environment variable

(*) perl is normally in /usr/bin/perl; if not but it is in your PATH, 
the executable perl scripts can be run with "perl [executable name 
here]".

== Current top-level scripts ==

Each script should have comments describing the input and output. Please 
note that some scripts may take up to a few hours to run on a modern 
laptop. If you write a script that takes significantly longer than this, 
please put a warning in its comments!

BUILD_ABERRATION_SENSITIVITIES:
  Reports to the user (stdout) a table of the coefficients of the 
sensitivities of the galaxy shear to each aberration (the "C" 
coefficients in the sensitivity matrix). Also reports, for each l-bin, 
the scaling factors (S-values) for that combination of aberrations. (The 
scripts in PSF_P1G1 must be run first.)

BUILD_PHOTO_PROPERTIES:
  Writes various parameters of the imaging survey in the shape 
measurement filters to scr/photopar.txt

CLEANUP:
  Removes temporary files that are not synchronized by GitHub (prompts 
user for removing each one)

MAKETAB_*:
  These scripts build the table .tex files in the TeX/ directory. The 
naming convention is that a table named \label{tab:XXX} in the TeX 
source should be in a file tab_XXX.tex in the TeX/ directory, built by 
the script MAKETAB_XXX in the top-level directory. The table .tex files 
are synchronized by GitHub so that users who haven't run the scripts can 
still read the paper. As a consequence, you should only use the 
MAKETAB_* scripts when you really need to update that table.

RUN_A0:
  This is the main script for computing additive and multiplicative 
systematics budgets, as described in the "Setting requirements" section 
of the paper.

SETUP_CLASS:
  This builds the WL power spectra needed by RUN_A0 (using CLASS). 
RUN_A0 can do this itself, but it takes time and is not implemented by 
many scripts calling RUN_A0. Therefore I recommend running SETUP_CLASS 
first, and then again if you change the z-bins or lmax (probably not 
frequent).

== Current directories with scripts and tools ==

PSF_P1G1:
  Galaxy sensitivity coefficients according to models P1 (PSF) and G1 
(shape measurement). You can build the coefficients with the "BUILD" 
script in this directory.
  The BUILD-JITTER script does the same for some additional scripts we
made for the referee report to Troxel et al. (2020).