How to order by multiple columns in pyspark - sorting

I have a data frame:-
Price sq.ft constructed
15000 800 22/12/2019
80000 1200 25/12/2019
90000 1400 15/12/2019
70000 1000 10/11/2019
80000 1300 24/12/2019
15000 950 26/12/2019
I want to sort multiple columns at once though I obtained the result I am looking for a better way to do it. Below is my code:-
df.select("*",F.row_number().over(
Window.partitionBy("Price").orderBy(col("Price").desc(),col("constructed").desc())).alias("Value")).display()
Price sq.ft constructed Value
15000 950 26/12/2019 1
15000 800 22/12/2019 2
70000 1000 10/11/2019 1
80000 1200 25/12/2019 1
80000 1300 24/12/2019 2
90000 1400 15/12/2019 1
Rather than repeating col("column name").desc() each time is there any better way to do it?
I have also tried the below way:-
df.select("*",F.row_number().over(
Window.partitionBy("Price").orderBy(["Price","constructed"],ascending = False).alias("Rank"))).display()
getting an error:-
TypeError: orderBy() got an unexpected keyword argument 'ascending'

You can use a list comprehension:
from pyspark.sql import functions as F, Window
Window.partitionBy("Price").orderBy(*[F.desc(c) for c in ["Price","constructed"]])

Related

Count number of connections in each network using DAX

I have a dataset like this in Power BI with connections between "Participant ID" Column and "Knows Participant":
Participant ID
Knows Participant
111
353
111
777
111
112
111
249
112
143
112
144
113
111
113
244
114
NaN
115
113
...
...
777
111
777
398
777
114
778
NaN
779
112
3499
NaN
I've build Network chart. However, there are a lot of 1-1 connections that are not very useful for visualization, so I want to exclude them (see image):
Is it possible to count a number of connections in each network using DAX and then use this value to filter out all nodes with only 1 connection (red circled)? Or maybe filter out 1 connection nodes using another approach?
I've tried to make a calculated column using DAX:
Connection Column = COUNTROWS(
FILTER(Table,
EARLIER(Table[Knows Participant])=Table[Knows Participant])
)
However, it only shows duplicate values in "Knows Participant" Column, but not number of connections in each network.
Example of desired output:
Participant ID
Knows Participant
Number of Connections in the Network
111
353
4
353
444
4
444
551
4
551
987
4
112
143
1
220
190
1
333
337
2
337
410
2
765
0
You need the PATH functions as you're essentially trying to flatten a hierarchy and then exclude certain parts of it. The following help page gives a good rundown of the approach to take.
https://learn.microsoft.com/en-us/dax/understanding-functions-for-parent-child-hierarchies-in-dax
You can add a column to the table with a measure like this:
VAR pIdLinksCount = CALCULATE(COUNTROWS(tbl), ALL('tbl'[Knows Participant]))
VAR neighbourLinksCount =
IF(
pIdLinksCount=1
, -- if pIdLinksCount=1 then count neighbour links
VAR neighbourId =
CALCULATETABLE(
Values('tbl'[Knows Participant])
)
RETURN
CALCULATE(
COUNTROWS(tbl)
,ALL() -- removes all filters from data model
,'tbl'[Participant ID] = neighbourId -- applies filter to [Participant ID] column
--,'tbl'[Participant ID] IN neighbourId -- alternatively try this. I believe it is not necessary
)
,2 -- returns 2 if pIdLinksCount>1.
-- The "value = 2" will return "result > 3 = TRUE()"
)
VAR result = pIdLinksCount + neighbourLinksCount
RETURN
IF(
result>2
,1
,0
)
The idea is to check a neighbor too - if it has more then 1 link

why my dxf file not working in AutoCAD giving me ID 11 incorrect: already used

I have generated a dxf file but when I opened it with AutoCAD, crashes AutoCAD and gives a message ID 11 incorrect: already used.
the dxf content: https://github.com/tarikjabiri/dxf/blob/dev/examples/latest.dxf
I can't spot the problem 3 days I am trying to solve it.
I think something wrong with the APPID because it holding the ID 11 or the Handle in the language of DXF.
I have a dxf working: https://github.com/tarikjabiri/dxf/blob/dev/examples/Minimal_DXF_AC1021.dxf
Thanks in advance.
There are two minor issues:
DIMSTYLE table
0
TABLE
2
DIMSTYLE
105 <<< handle group code of the table "head" is 5 as usual
8
100
AcDbSymbolTable
100
AcDbDimStyleTable
70
1
0
DIMSTYLE
5 <<< handle group code of the table entry is 105
12
330
8
100
AcDbSymbolTableRecord
100
AcDbDimStyleTableRecord
2
STANDARD
70
0
40
1
BLOCK_RECORD table entries for *MODEL_SPACE and *PAPER_SPACE
0
TABLE
2
BLOCK_RECORD
5
9
330
0
100
AcDbSymbolTable
70
2
0
BLOCK_RECORD
5
14
330
9
100
AcDbSymbolTableRecord
100
AcDbRegAppTableRecord <<< subclass marker string "AcDbBlockTableRecord"
2
*MODEL_SPACE
70
0
70
0
280
After this changes the file opens in Autodesk DWG Trueview 2022.

How to round off seconds to the nearest minute?

I am converting [ss] seconds to mm:ss format.
But, I also have to round off the value to the nearest minute.
For example, 19:29 -> 19 minutes and 19:32-> 20 minutes
I have tried using mround function. But it did not work.
=MROUND(19.45,15/60/24) gives output as 19.44791667.
It should come as 20 seconds.
try like this where B column is formatted as Time
=ARRAYFORMULA(IF(LEN(A1:A), MROUND(A1:A, "00:01:00"), ))
=TEXT(MROUND("00:"&TO_TEXT(B5), "00:01:00"), "mm:ss")
=ARRAYFORMULA(TEXT(MROUND(SUM(TIME(0,
REGEXEXTRACT(TO_TEXT(C3:C11), "(.+):"),
REGEXEXTRACT(TO_TEXT(C3:C11), ":(.+)"))), "00:01:00"), "[mm]:ss"))

Spark SQL performance too slow if the number of rows are 100000

I'm testing Spark performance with very many rows table.
What I did is very simple.
Prepare csv file which has many rows and only 2 data records.
eg, csv file is like as follows:
col000001,col000002,,,,,,,col100000
dtA000001,dtA000002,,,,,,,,dtA100000
dtB000001,dtB000002,,,,,,,,dtB100000
dfdata100000 = sqlContext.read.csv('../datasets/100000c.csv', header='true')
dfdata100000.registerTempTable("tbl100000")
result = sqlContext.sql("select col000001,ol100000 from tbl100000")
Then get 1 row by show(1)
%%time
result.show(1)
File sizes are as follows(very small).
File name shows the number of rows:
$ du -m *c.csv
3 100000c.csv
1 10000c.csv
1 1000c.csv
1 100c.csv
1 20479c.csv
2 40000c.csv
2 60000c.csv
3 80000c.csv
Results are like as follows:
As you can see, the execution time is exponentially increase.
Example result:
+---------+---------+
|col000001|col100000|
+---------+---------+
|dtA000001|dtA100000|
+---------+---------+
only showing top 1 row
CPU times: user 218 ms, sys: 509 ms, total: 727 ms
Wall time: 53min 22s
Question1: Is it an acceptable result? Why is the execution time exponentially increase?
Question2: Is there any other method to do faster?

PIG - retrieve data from XML using XPATH

I have n number of these type of xml files.
<students roll_no=1>
<name>abc</name>
<gender>m</gender>
<maxmarks>
<marks>
<year>2014</year>
<maths>100</maths>
<english>100</english>
<spanish>100</spanish>
<marks>
<marks>
<year>2015</year>
<maths>110</maths>
<english>110</english>
<spanish>110</spanish>
<marks>
</maxmarks>
<marksobt>
<marks>
<year>2014</year>
<maths>90</maths>
<english>95</english>
<spanish>82</spanish>
<marks>
<marks>
<year>2015</year>
<maths>94</maths>
<english>98</english>
<spanish>02</spanish>
<marks>
</marksobt>
</Students>
I need output like
roll_no name gender year eng_max_marks maths_max_marks spanish_max_marks
1 abc m 2014 100 100 100
1 abc m 2015 110 110 110
I am able to retrieve marks row wise in single statement but not able to extract roll_no and name with this.
A = LOAD 'student.xml' using org.apache.pig.piggybank.storage.XMLLoader('marks') as (x:chararray);
B = FOREACH A GENERATE XPath(x, 'marks/year'), XPath(x, 'marks/english'), XPath(x, 'marks/math'), XPath(x, 'marks/spanish');
This return
year eng_max_marks maths_max_marks spanish_max_marks
2014 100 100 100
2015 110 110 110
I can extract both the chunks but not getting how to join other fields. I can't use across join because I have n number of other files.
Let's forger attribute name (roll_no) for now. How can I extract the rest of nodes
name gender year eng_max_marks maths_max_marks spanish_max_marks
abc m 2014 100 100 100
abc m 2015 110 110 110
I don't want to use marks(1)/english approach because this nodes can also vary and don't want to adopt any dirty approach.
Any pointers????

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