I need to count the number of zero elements in numpy arrays. I'm aware of the numpy.count_nonzero function, but there appears to be no analog for counting zero elements. My arrays are not very large (typically less than 1E5 elements) but the operation is performed several millions of times.

Feb 10, 2013 · I'm trying to return the number of appointments a person has (including if they have zero). Appointment contains the person_id and there is a person_id per appointment. So COUNT(person_id) is a sensible approach. The query: SELECT person_id, COUNT(person_id) AS "number_of_appointments" FROM appointment GROUP BY person_id;

Nov 7, 2011 · Note that we're taking advantage of the fact that COUNT() will only count non-NULL values to get a 0 COUNT result for those result set records that are made up only of data from the new ProjectYears table. Alternatively, you might only one 0 count record to be returned per project (or maybe one per financial_year). You would modify the above ...

Jul 20, 2012 · Pivot table is counting zeros: in my table, I have stores in column A, item name in column B and units sold in column C. I need a count of stores that sold at least 1 piece, so a count that doesn't include zeros. What is best way to acheive in …

There is a way to count the number of columns that have zeros. This one uses dplyr . First, data.frame operation mode needs to be rowwise() then, columns must be subset with c_across() which returns a vector, that can be used in any function that takes vectors.

Mar 11, 2015 · You can use opencv's function countNonZero for counting the number of non-zero pixels in the image. img3 = doCanny(img2, 10, 100, 3) nzCount = cv.CountNonZero(img3); Update:

Mar 20, 2008 · Hi, Is there a way to make a Pivot Table NOT count zero values, and just show them as (blank)? All my 0 values are being counted in the data field as "1", which is contaminating the grand totals. Thanks,

May 3, 2016 · df.groupby(['Symbol','Year']).count() I get . Action Symbol Year AAPL 2001 2 BAC 2002 2 I desire this (order does not matter) Action Symbol Year AAPL 2001 2 AAPL 2002 0 BAC 2001 0 BAC 2002 2 I want to know if its possible to count for zero occurances

May 16, 2015 · I am looking to count the number of times the values in an array change in polarity (EDIT: Number of times the values in an array cross zero). Suppose I have an array: [80.6 120.8 -115.6 -76....

Jun 22, 2011 · This is a comment I posted above: I have no idea why NZ(Count([Issue Mgt].ID))+0 would be preferred to NZ(Count([Issue Mgt].ID,0). Please explain. That is, when you omit the second argument for Nz(), you are taking your chances as to what you'll get, and by adding 0 you're implicitly coercing it to a numeric value.