Tips for tract definition

Using same tract for all data

The common tract is defined when you select all data and run makeDiscreteSkyMap.py. You can make the data which have same positional information using the common tract. If you do not select all visit and filter for which you execute multiband analysis, it does not succeed


Using user-defined patch size

You can configure the patch size according to your interests.

For example, if you change the size as patch = tract, add the option shown below.

# Define new tract (patch size = tract size)
makeDiscreteSkyMap.py $home/hsc --calib=$home/hsc/CALIB/ --rerun=test --id field=M31 --config doAppend=True skyMap.patchInnerDimensions="[50000,50000]"

# Options：
#    --config
#        doAppend=True                              ：Add new tract. If you run makeDiscreteSkyMap.py for the first time in the analysis, no need to add.
#        skyMap.patchInnerDimensions="[50000,50000]"： Specify patch pixel size. Set large size to be patch = tract.

In case that you have already performed makeDiscreteSkyMap.py and defined tract=0, you have to define a new tract again to add doAppend=True. The number of pixel will be different in each data, please try some cases.

Warning

It is possible to define 1 patch = 1 tract, though it will stop warp processing due to lack of memory during coaddDriver.py or make command execution slower.

Warning

One TAN projection is used in one tract. So if you define large tract, please be careful of the effect to your target science.


Defining tract based on coordinate information

A tract is defined based on observed data in makeDiscreteSkyMap.py. On the other hand, the tract can be also defined based on the grid on the celestial sphere. The hscPipe command makeSkyMap.py is used. When you use it, you need to prepare a configuration file in which the definition of the tract is written.

The following case is running makeSkyMap.py with configuration file named overrides.config.

# Write the following lines in overrides.config.
cat overrides.config

===
root.skyMap = "discrete"
root.skyMap["discrete"].raList = [149.9]
root.skyMap["discrete"].decList = [2.3]
root.skyMap["discrete"].radiusList = [0.35]
root.skyMap["discrete"].pixelScale = 0.2
root.skyMap["discrete"].projection = "TAN"
root.skyMap["discrete"].tractOverlap = 0
===


# Execute makeSkyMap.py with your config file.
makeSkyMap.py $home/hsc --rerun test --configfile overrides.config

# Usage：
#   makeSkyMap.py [data reduction directory]　--rerun [rerun name] --configfile [config file]

Defining tract same as SSP

Execute makeSkyMap.py without any options.

makeSkyMap.py [data reduction directory]  --calib=~HSC/CALIB　--rerun [rerun name]