How to import PV curve data into a .txt file?

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Hello, please see the follow code, this is for exporting the data of "QV curves" to excel file. Also, you can check the file in "Example"/"pssexcel_demo.py". Hope you can solve the problem!

qvfile  = 'filename.qv'
string  = ['s','v','m','g']
colabel = []
p, nx   = os.path.split(qvfile)
n, x    = os.path.splitext(nx)
xlsfile = 'filename'
sheet   = n + '_qv'
overwritesheet = True
pssexcel.qv(qvfile,string,colabel=colabel,xlsfile=xlsfile,sheet=sheet,overwritesheet=overwritesheet,show=True)

I use scripts like this to extract data for a *.pv file:

def get_volts(pvfile, colabel):
    "Return volts for a contingency"
    pvobj = arrbox.pv_pp.PV_PP(pvfile)
    summ = pvobj.summary()
    solnobj = pvobj.solution(colabel=colabel)

    return pd.DataFrame(
        index=solnobj.mwtransfer,
        columns=summ.mvbuslabel,
        data=solnobj.volts
    )


def get_amps(pvfile, colabel):
    "Return I as MVA"
    pvobj = arrbox.pv_pp.PV_PP(pvfile)
    summ = pvobj.summary()
    solnobj = pvobj.solution(colabel=colabel)

    return pd.DataFrame(
        index=solnobj.mwtransfer,
        columns=summ.mbranch,
        data=solnobj.mbrnamp
    )