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When I try to use GeoIdentify in dynamic mode. It doesn't work. For example, I want to show the country name when mouse hover on Canada in GeoGraphic. It just print out the empty list. It there any way to solve this problem? { ...
Recently, I have read the section of Date and Times in An Elementary Introduction of Wolfram Language. This section has mentioned a function called WordFrequencyData. I had tried some words to observe the word frequency in time series based. For...
If i change the format of the equation It will output the result  I want I don't know why it would produce the different results f[t_] = r2 E^(I q2[t]) + r3[t] E^(I q3[t]) - r1 E^(I q1[t]) f2 = f'[t] // ComplexExpand