powerquery: extra digits added to number when importing table - powerbi

Glad to ask a question here again after more than 10 years (last one was about BASH scripting, now as I'm in corporate, guess what... it's about excel ;) )
here it's my question/issue:
I am importing data with powerquery for further analysis
I have discovered is that the values imported contains extradigits not present in the original table.
I have googled for this problem but I have not been able to find an explanation nor a solution ( a similar issue is this one this one , more than one year old, but with no feedback from Microsoft )
(columns are formatted as text in the screenshot but the issue is still present even if formatted as number)
The workaround I am using now, but I am not happy with that is the following:
I "increased decimal" to make sure all my digits are captured (in my source the entries do not have all the same significant digits),
saved as csv
imported impacted columns as number
convert columns as text (for future text match
I am really annoyed by this unwanted and unpredictable behaviour of excel.
I see a serious issue of data integrity, if we cannot rely on the powerquery/powerbi platform to maintain accurate queries, I wonder why would be use it
adding another screenshot to clarify that changing the source format to text does not solve the problem
another screenshot added following #David Bacci comments:
I think I wrongfully assumed my data was stored as text in the source, can you confirm?

If you are exporting and importing as text, then this will not happen. If you convert to number, you will lose precision. From the docs (my bold):
Represents a 64-bit (eight-byte) floating-point number. It's the most
common number type, and corresponds to numbers as you usually think of
them. Although designed to handle numbers with fractional values, it
also handles whole numbers. The Decimal Number type can handle
negative values from –1.79E +308 through –2.23E –308, 0, and positive
values from 2.23E –308 through 1.79E + 308. For example, numbers like
34, 34.01, and 34.000367063 are valid decimal numbers. The largest
precision that can be represented in a Decimal Number type is 15
digits long. The decimal separator can occur anywhere in the number.
The Decimal Number type corresponds to how Excel stores its numbers.
Note that a binary floating-point number can't represent all numbers
within its supported range with 100% accuracy. Thus, minor differences
in precision might occur when representing certain decimal numbers.
BTW, you should probably accept some of the good answers from your previous questions from 10 years ago.

Related

Identify the value with highest number of decimal values

I have a range of values and I want to count the decimal points of all values in the range and display the max count. the formula should exclude the zeroes at the end(not count ending zeroes in the decimal points).
for example, in the above sample, in the whole range the max of count of decimal places is 4 excluding the ending zeroes. so the answer is 4 to be displayed in cell D2
I tried doing regex, but do not know how do I do it for a whole range of values.
Please help!
try:
=INDEX(MAX(LEN(IFERROR(REGEXEXTRACT(TO_TEXT(A2:C4), "(\..+)")*1))-2))
Player0's solution is a good start, but uses TO_TEXT which seems to rely on the formatting of your cells.
If you want to safely compute the number of decimal places, use the TEXT function instead.
TEXT(number, format) requires a format whose max. number of decimal places has to be specified. There is no way around this, because formulas like =1/3 can have infinitely many decimal places.
Therefore, first decide on the max, precision for your use-case (here we use 8). Then use below function which works independently from your document's formatting and language:
=INDEX(MAX(
LEN(REGEXEXTRACT(
TEXT(ABS(A2:C4); "."&REPT("#";8));
"[,.].*$"
))-1
))
We subtract -1 since LEN(REGEXEXTRACT()) also counts the decimal separator (. for english, , for many others) .
Everything after the 8th decimal place is ignored. If all your numbers are something like 123.00000000987 the computed max. is 0. If you prefer it to be 8 instead, then add ROUNDUP( ; 8):
=INDEX(MAX(
LEN(REGEXEXTRACT(
TEXT(ROUNDUP(ABS(A2:C4);8); "."&REPT("#";8));
"[,.].*$"
))-1
))

One decimal field taking up 75% file size of power bi file

I have a Power bi file which is over a 2gb in size and found one field is taking up 1.5gb of the file size. When I change it to a whole number or decimal it is reduced to 350mb.
I wanted to change to a decimal but I feel it being changed to a decimal place shouldn't increase the file size so dramatically. Is this correct and wanted to check if this is expected behaviour
Thanks for any help
Here is a screenshot of the settings:
If you are ok with only preserving 4 decimals then you can switch to a “fixed decimal number” data type and it should compress the same as a whole number. Fixed decimal is stored as an integer and the last 4 digits are interpreted to be right of the decimal as explained here.

Controlling newlines when writing out arrays in Fortran

So I have some code that does essentially this:
REAL, DIMENSION(31) :: month_data
INTEGER :: no_days
no_days = get_no_days()
month_data = [fill array with some values]
WRITE(1000,*) (month_data(d), d=1,no_days)
So I have an array with values for each month, in a loop I fill the array with a certain number of values based on how many days there are in that month, then write out the results into a file.
It took me quite some time to wrap my head around the whole 'write out an array in one go' aspect of WRITE, but this seems to work.
However this way, it writes out the numbers in the array like this (example for January, so 31 values):
0.00000 10.0000 20.0000 30.0000 40.0000 50.0000 60.0000
70.0000 80.0000 90.0000 100.000 110.000 120.000 130.000
140.000 150.000 160.000 170.000 180.000 190.000 200.000
210.000 220.000 230.000 240.000 250.000 260.000 270.000
280.000 290.000 300.000
So it prefixes a lot of spaces (presumably to make columns line up even when there are larger values in the array), and it wraps lines to make it not exceed a certain width (I think 128 chars? not sure).
I don't really mind the extra spaces (although they inflate my file sizes considerably, so it would be nice to fix that too...) but the breaking-up-lines screws up my other tooling. I've tried reading several Fortran manuals, but while some of the mention 'output formatting', I have yet to find one that mentions newlines or columns.
So, how do I control how arrays are written out when using the syntax above in Fortran?
(also, while we're at it, how do I control the nr of decimal digits? I know these are all integer values so I'd like to leave out any decimals all together, but I can't change the data type to INTEGER in my code because of reasons).
You probably want something similar to
WRITE(1000,'(31(F6.0,1X))') (month_data(d), d=1,no_days)
Explanation:
The use of * as the format specification is called list directed I/O: it is easy to code, but you are giving away all control over the format to the processor. In order to control the format you need to provide explicit formatting, via a label to a FORMAT statement or via a character variable.
Use the F edit descriptor for real variables in decimal form. Their syntax is Fw.d, where w is the width of the field and d is the number of decimal places, including the decimal sign. F6.0 therefore means a field of 6 characters of width with no decimal places.
Spaces can be added with the X control edit descriptor.
Repetitions of edit descriptors can be indicated with the number of repetitions before a symbol.
Groups can be created with (...), and they can be repeated if preceded by a number of repetitions.
No more items are printed beyond the last provided variable, even if the format specifies how to print more items than the ones actually provided - so you can ask for 31 repetitions even if for some months you will only print data for 30 or 28 days.
Besides,
New lines could be added with the / control edit descriptor; e.g., if you wanted to print the data with 10 values per row, you could do
WRITE(1000,'(4(10(F6.0,:,1X),/))') (month_data(d), d=1,no_days)
Note the : control edit descriptor in this second example: it indicates that, if there are no more items to print, nothing else should be printed - not even spaces corresponding to control edit descriptors such as X or /. While it could have been used in the previous example, it is more relevant here, in order to ensure that, if no_days is a multiple of 10, there isn't an empty line after the 3 rows of data.
If you want to completely remove the decimal symbol, you would need to rather print the nearest integers using the nint intrinsic and the Iw (integer) descriptor:
WRITE(1000,'(31(I6,1X))') (nint(month_data(d)), d=1,no_days)

Meaning of 3F7.1 in Fortran data format

I am trying to create an MDM file using HLM 7 Student version, but since I don't have access to SPSS I am trying to import my data using ASCII input. As part of this process I am required to input the data format Fortran style. Try as I might I have not been able to understand this step. Could someone familiar with Fortran (or even better HLM itself) explain to me how this works? Here is my current understanding
From the example EG3.DAT they give
(A4,1X,3F7.1)
I think
A4 signifies that the ID is 4 characters long.
1X means skip a space.
F.1 means that it should read 1 decimal places.
I am very confused about what 3F7 might mean.
EG3.DAT
2020 380.0 40.3 12.5
2040 502.0 83.1 18.6
2180 777.0 96.6 44.4
Below are examples from the help documents.
Rules for format statement
Format statement example
EG1 data format
EG2 data format
EG3 data format
One similar question is Explaining Fortran Write Format. Unfortunately it does not explicitly treat the F descriptor.
3F7.1 means 3 floating point numbers, each printed over 7 characters, each with one decimal number behind the decimal point. Leading characters are blanks.
For reading you don't need the .1 info at all, just read a floating point number from those 7 characters.
You guessed the meaning of A4 (string of four characters) and 1X (one blank) correctly.
In Fortran, so-called data edit descriptors (which format the input or output of data) may have repeat specifications.
In the format (A4,1X,3F7.1) the data edit descriptors are A4 and F7.1. Only F7.1 has a repeat specification (the number before the F). This simply means that the format is as though the descriptor appeared repeated: like F7.1, F7.1, F7.1. With a repeat specification of 1, or not given, there is just the single appearance.
The format of the question, then, is like
(A4,1X,F7.1,F7.1,F7.1)
This format is one that is covered by the rules provided in one of the images of the question. In particular, the aspect of repeat specification is given in rule 2 with the corresponding example of rule 3.
Further, in Fortran proper, a repeat count specifier may also be * as special case: that's like an exceptionally large repeat count. *(F7.1) would be like F7.1, F7.1, F7.1, .... I see no indication that this is supported by HLM but if this is needed a very large repeat count may be given instead.
In 1X the 1 isn't a repeat specification but an integral, and necessary, part of the position edit descriptor.
Procedure for making MDM file from excel for HLM:
-Make sure ALL the characters in ALL the columns line up
Select a column, then right click and select Format Cells
Then click on 'Custom' and go to the 'Type' box and enter the number
of 0s you need to line everything up
-Remove all the tabs from the document and replace them with spaces.
Open the document in word and use find and replace
-To save the document as .dat
First save it as .txt
Then open it in Notepad and save it as .dat
To enter the data format (FORTRAN-Style)
The program wants to read the data file space by space, so you have to specify it perfectly so that it reads the whole set properly.
If something is off, even by a single space, then your descriptive stats will be wonky compared to if you check them in another program.
Enclose the code with brackets ()
Divide the entries with commas ,
-Need ID column for all levels
ID column needs to be sorted so that it is in order from smallest to
largest
Use A# with # being the number of characters in the ID
Use an X1 to
move from the ID to the next column
-Need to say how many characters are needed in each column
Use F
After F is the number of characters needed for that column -Use F# (#= number)
There need to be enough character spaces to provide one 'gap' space
between each column
There need to be enough to character spaces to allow for the decimal
As part of the F you need to specify the number of decimal places
You do this by adding a decimal point after the F number and then a
number to represent the spaces you need -F#.#
You can use a number in front of the F so as to 'repeat' it. Not
necessary though. -#F#.#
All in all, it should look something like this:
(A4,X1,F4.0,F5.1)
Helpful links:
https://books.google.de/books?id=VdmVtz6Wtc0C&pg=PA78&lpg=PA78&dq=data+format+fortran+style+hlm&source=bl&ots=kURJ6USN5e&sig=fdtsmTGSKFxn04wkxvRc2Vw1l5Q&hl=en&sa=X&ved=0ahUKEwi_yPurjYrYAhWIJuwKHa0uCuAQ6AEIPzAC#v=onepage&q&f=false
http://www.ssicentral.com/hlm/help6/error/Problems_creating_MDM_files.pdf
http://www.ssicentral.com/hlm/help7/faq/FAQ_Format_specifications_for_ASCII_data.pdf

What is SAS format 8.

I am new to SAS and currently working on a small piece of work with SAS.
Could I please ask what the below format means? I believe the 8. is formatting two digits to the right of the decimal place such as 896.33 but I am not sure. Not really sure what input means.
input(tablename.fieldname, 8.)
That is an INFORMAT, not a FORMAT. It means to read the first 8 characters as a number. If there is a decimal point in the data then it is used naturally. You could have up to 7 digits to the right of the decimal point (since the decimal point would use up the eighth character position). It will also support reading scientific notation so '896.33E2' would mean the number 89,633.