This question already has answers here:
How to find median and quantiles using Spark
(8 answers)
Closed 5 years ago.
Say I have a dataframe that contains cars, their brand and their price. I would like to replace the avg below by median (or another percentile):
df.groupby('carBrand').agg(F.avg('carPrice').alias('avgPrice'))
However, it seems that there is no aggregation function that allows to compute this in Spark.
You can try the approxQuantile function (see http://spark.apache.org/docs/latest/api/python/pyspark.sql.html#module-pyspark.sql.functions)
Related
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MS Access query, how to use SQL to group single dates into weeks
(2 answers)
VBA Convert date to week number
(8 answers)
Closed 2 years ago.
I have an access-file, that I imported in excel as a PivotTable. I want the possibility to sort the data in a slicer as Week numbers. I have grouped and set days to 7, but that only gives me 2020-01-01 - 2020-01-07 for example.
Should I convert the weeknum's already in Access? And then, how do I do that?
Please explain it all, even where to paste the code and how to implement it in Access.
Thank you.
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How do I expand the output display to see more columns of a Pandas DataFrame?
(22 answers)
Closed 3 years ago.
I have a dataset with 200000 rows and 201 columns. I want to have descriptive statistics of all the variables.
I tried:
'''train.describe()'''
But this is only giving the output for the first and last 8 variables. This there any method I can use to get the statistics for all of the columns.
probably, some of your columns where in some type other than numerical. Try train.apply(pd.to_numeric) then train.describe()
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Count on Spark Dataframe is extremely slow
(2 answers)
Getting the count of records in a data frame quickly
(2 answers)
Closed 3 years ago.
I have a very large pyspark dataframe and I would calculate the number of row, but count() method is too slow. Is there any other faster method?
If you don't mind getting an approximate count, you could try sampling the dataset first and then scaling by your sampling factor:
>>> df = spark.range(10)
>>> df.sample(0.5).count()
4
In this case, you would scale the count() results by 2 (or 1/0.5). Obviously, there is an statistical error with this approach.
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How to roundup a number to the closest ten?
(4 answers)
Closed 6 years ago.
How to round up a number to the nearest .5 in excel?
For example round up number 77.2 to 77.5.
CEILING(number, significance)
Number - The value you want to round.
Significance -The multiple to which you want to round.
Returns number rounded up, away from zero, to the nearest multiple of significance. For example, if you want to avoid using pennies in your prices and your product is priced at $4.42, use the formula =CEILING(4.42,0.05) to round prices up to the nearest nickel.
So, in your case:
CEILING(value, 0.5)
More info on Microsoft support
This question already has answers here:
Excel formula to do the same as x=(b/N)*(-floor(N/2):floor(N/2)) in MATLAB
(2 answers)
Closed 8 years ago.
The 'floor' command in MATLAB is defined as "Round towards minus infinity.
floor(X) rounds the elements of X to the nearest integers
towards minus infinity."
Is there a similar command within Excel, or does anyone know how to perform the same action within Excel?
yes, you can use =INT(A1) formula. It rounds a number (from A1 cell) down to the nearest integer. Here is documentation.