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Practice of dm-script build-in function: icol & calibration information

Using icol function to create peak.

 Gaussian peak
I=A*exp((x-mu)^2/(2*sigma^2)
where mu is the peak center
           sigma is the divergence of the peak

 --

 image img=RealImage("peak",4,1024,1)

 //  peak 1 parameters
// N_K edge
number int1=30
number mu1=300
number sig1=5

 // peak 2 parameters
// O_K edge
number int2=150
number mu2=432
number sig2=0.9

 number int3=50
number mu3=438
number sig3=2.5

 // add noise
number noise=0.5

 // EELS signal creation
img=int1*exp(-1*(icol-mu1)**2/(2*sig1**2))
img+=int2*exp(-1*(icol-mu2)**2/(2*sig2**2))
img+=int3*exp(-1*(icol-mu3)**2/(2*sig3**2))
img+=0.05*exp(10-icol/100)+noise*int1*random()

 // Write calibration
img.ImageSetDimensionOrigin(0,100)
img.ImageSetDimensionScale(0,1)
img.ImageSetDimensionUnitString(0, "eV" )
img.ImageSetIntensityUnitString( "e-" )
img.setname("Test Spec + " + noise*100 + "% noise")
img.showimage()

 --

 Result
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