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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 2.4 External Tools
The following section demonstrates how to use the signac command line interface (CLI) in conjunction with other tools.
Step1:  To interact with a project on the command line, the current working directory needs to be within or below the project root directory.
Let's start by reseting the designated project root directory for this section of the tutorial.
Step2:  Next we switch the current working directory to the project root directory.
Step3:  Then we initialize the project.
Step4:  We can verify the project configuration.
Step5:  We access the job handle by providing the state point on the command line in JSON format.
Step6:  The statepoints could also be read from STDIN, e.g., by reading it from a file.
Let's create a statepoints file with three statepoints
Step7:  We can pipe the content of this file into the signac CLI to get the corresponding job id.
Step8:  Instead of the job id, we can directly obtain the path to the job workspace.
Step9:  That's specifically useful in conjunction with external tools.
Let's pretend that we need to use a program called idg to calculate the ideal gas equation.
The idg program will calculate the volume of an ideal gas given the input parameters p, kT and N, just like in the previous sections.
Step10:  We can store the result in a file based on the input arguments using the -cw argument, short for --create --workspace, which returns the workspace path and creates it if necessary.
Step11:  Obviously, we wouldn't write these commands all manually, but use a script instead.
Step12:  We can then execute this script...
Step13:  ... and examine the results.
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Python Code:
%%bash
signac --help
Explanation: 2.4 External Tools
The following section demonstrates how to use the signac command line interface (CLI) in conjunction with other tools.
End of explanation
% pwd
% rm -rf projects/tutorial/cli
% mkdir -p projects/tutorial/cli
% cp idg projects/tutorial/cli
Explanation: To interact with a project on the command line, the current working directory needs to be within or below the project root directory.
Let's start by reseting the designated project root directory for this section of the tutorial.
End of explanation
% cd projects/tutorial/cli
Explanation: Next we switch the current working directory to the project root directory.
End of explanation
%%bash
signac init TutorialCLIProject
Explanation: Then we initialize the project.
End of explanation
%%bash
signac project
signac project --workspace
Explanation: We can verify the project configuration.
End of explanation
%%bash
signac job '{"kT": 1.0, "p": 1.0, "N": 1000}'
Explanation: We access the job handle by providing the state point on the command line in JSON format.
End of explanation
%%bash
echo '{"kT": 1.0, "p": 0.1, "N": 1000}' > statepoints.txt
echo '{"kT": 1.0, "p": 1.0, "N": 1000}' >> statepoints.txt
echo '{"kT": 1.0, "p": 10.0, "N": 1000}' >> statepoints.txt
cat statepoints.txt
Explanation: The statepoints could also be read from STDIN, e.g., by reading it from a file.
Let's create a statepoints file with three statepoints:
End of explanation
%%bash
head -n 1 statepoints.txt | signac job
Explanation: We can pipe the content of this file into the signac CLI to get the corresponding job id.
End of explanation
%%bash
head -n 1 statepoints.txt | signac job --workspace
Explanation: Instead of the job id, we can directly obtain the path to the job workspace.
End of explanation
%%bash
./idg -p 1.0 -N 1000 --kT 1.0
Explanation: That's specifically useful in conjunction with external tools.
Let's pretend that we need to use a program called idg to calculate the ideal gas equation.
The idg program will calculate the volume of an ideal gas given the input parameters p, kT and N, just like in the previous sections.
End of explanation
%%bash
./idg -p 1.0 --kT 1.0 -N 1000 > $(signac job -cw '{"p": 1.0, "kT": 1.0, "N": 1000}')/V.txt
Explanation: We can store the result in a file based on the input arguments using the -cw argument, short for --create --workspace, which returns the workspace path and creates it if necessary.
End of explanation
import signac
import json
project = signac.get_project()
for p in 0.1, 1.0, 10.0:
    job = project.open_job({'N': 1000, 'p': p, 'kT': 1.0})
    cmd = './idg -p {p} --kT {kT} -N {N}'.format(**job.statepoint())
    cmd += " > $(signac job -cw '{}')/V.txt".format(json.dumps(job.statepoint()))
    print(cmd)
Explanation: Obviously, we wouldn't write these commands all manually, but use a script instead.
End of explanation
%%bash
./idg -p 0.1 --kT 1.0 -N 1000 > $(signac job -cw '{"kT": 1.0, "p": 0.1, "N": 1000}')/V.txt
./idg -p 1.0 --kT 1.0 -N 1000 > $(signac job -cw '{"kT": 1.0, "p": 1.0, "N": 1000}')/V.txt
./idg -p 10.0 --kT 1.0 -N 1000 > $(signac job -cw '{"kT": 1.0, "p": 10.0, "N": 1000}')/V.txt
Explanation: We can then execute this script...
End of explanation
% cat `signac project -w`/*/V.txt
Explanation: ... and examine the results.
End of explanation
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