I am very to new to Julia. Therefore, please excuse me if this is a silly problem.I have a 4*4 Matrix AA.

## Pandas dataframe drop columns with no header

What's the most pythonic place to drop the columns in a dataframe where the header row is NaN? Preferably inplace.

## Why does nansum work for input that exceeds matrix dimensions?

I am wondering about matlab's nansumfunction.When I use the example from the documentationand then call

## Java – String.lastIndexOf(str) logic I cannot understand

I used two different string to test the last index of "/t", but they both return 4. I thought it should be 5 and 4. I checked the oracle docs and I could not understand why. Could someone please tell me why? Thank you!

## Create matrix row-index which increments when rowsum > 100, and following row

I have a matrix:I want to add a column with rows index. This index will starts at 1 and repeats the same index, until it arrived to a row where the rowsums is > 100 to move to the next value.

## In MATLAB, how to find indexes in vector every time value change from 1 to 0?

I have a vector of 1s and 0s that represent when an intermittent data signal is occurring. E.g.:How do I find the index value of every change from 1 to 0? So for vector V above, the answer would be:

## Checking that a pandas.Series.index contains a value

I (think I) know how to check if a value is contained in the index of a pandas Series, but I can't get it to work in the example below. Is it a bug perhaps?