why does union of two dataframes give less count - pyspark

I have two dataframes and when I union them, I got less rows/counts.
col_names = ["city", "name"]
print(df1.select(col_names)).count()) # 50
print(df2.select(col_names)).count()) # 60
df1.select(col_names).union(df2.select(col_names)).count() # 105
df1.select(col_names).unionByName(df2.select(col_names)).count() # 105
But if I recreate both dataframes, everything is right
col_names = ["city", "name"]
df1_new = spark.createDataFrame(df1.select(col_names).head(50))
df2_new = spark.createDataFrame(df2.select(col_names).head(60))
print(df1_new.select(col_names)).count()) # 50
print(df2_new.select(col_names)).count()) # 60
df1_new.union(df2_new).count() # 110
df1_new.unionByName(df2_new).count() # 110
I also tried pandas by using pd.concat and it also worked. So it really confuses me.
Could anyone shed some light on why this happens?

Run an explain on
df1_new.union(df2_new).explain()
and
df1.select(col_names).union(df2.select(col_names)).explain()
It will show you what the difference between these two sets.

Related

Substring function to extract part of the string

data = {'desc': ['ADRIAN PETER - ANN 80020355787C - 11 Baillon Pass.pdf', 'AILEEN MARCUS - ANC 800E15432922 - 5 Mandarin Way.pdf',
'AJITH SINGH - ANN 80020837750 - 11 Berkeley Loop.pdf', 'ALEX MARTIN-CURTIS - ANC 80021710355 - 26 Dovedale St.pdf',
'Alice.Smith\Jodee - Karen - ANE 80020428377 - 58 Harrisdale Dr.pdf']}
df = pd.DataFrame(data, columns = ['desc'])
df
From the data frame, I want to create a new column called ID, and in that ID, I want to have only those values starting after ANN, ANC or ANE. So I am expecting a result as below.
ID
80020355787C
800E15432922
80020837750
80021710355
80020428377
I tried running the code below, but it did not get the desired result. Appreciate your help on this.
df['id'] = df['desc'].str.extract(r'\-([^|]+)\-')
You can use - AN[NCE] (800[0-9A-Z]+) -, where:
AN[NCE] matches literally AN followed by N or C or E;
800[0-9A-Z]+ matches literally 800 followed by one or more characters between 0 and 9 or between A and Z.
>>> df['desc'].str.extract(r'- AN[NCE] (800[0-9A-Z]+) -')
0
0 80020355787C
1 800E15432922
2 80020837750
3 80021710355
4 80020428377
If not all your ids start with "800", you can just remove it from the pattern.

Regular expression for MS SQL

I want arrange these numbers first two numbers into following categories i confuse because it repeats it self.
Thank you fo your help.
210690, 391910, 392490, 880390, 847321, 940290, 300420, 300410, 901890, 901890, 030269,080530, 630399
1-5
6-14
5
16-24
25-27
28-38
39-40
41-41
44-46
47-49
50-63
64-67
68-70
71
72-83
84-85
86-89
90-92
93
94-96
97
98-99

Marginal Means accounting for the random effect uncertainty

When we have repeated measurements on an experimental unit, typically these units cannot be considered 'independent' and need to be modeled in a way that we get valid estimates for our standard errors.
When I compare the intervals obtained by computing the marginal means for the treatment using a mixed model (treating the unit as a random effect) and in the other case, first averaging over the unit and THEN runnning a simple linear model on the averaged responses, I get the exact same uncertainty intervals.
How do we incorporate the uncertainty of the measurements of the unit, into the uncertainty of what we think our treatments look like?
In order to really propogate all the uncertainty, shouldn't we see what the treatment looks like, averaged over "all possible measurements" on a unit?
``` r
library(dplyr)
#>
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#>
#> filter, lag
#> The following objects are masked from 'package:base':
#>
#> intersect, setdiff, setequal, union
library(emmeans)
library(lme4)
#> Loading required package: Matrix
library(ggplot2)
tmp <- structure(list(treatment = c("A", "A", "A", "A", "A", "A", "A",
"A", "A", "A", "A", "A", "B", "B", "B", "B", "B", "B", "B", "B",
"B", "B", "B", "B"), response = c(151.27333548, 162.3933313,
159.2199999, 159.16666725, 210.82, 204.18666667, 196.97333333,
194.54666667, 154.18666667, 194.99333333, 193.48, 191.71333333,
124.1, 109.32666667, 105.32, 102.22, 110.83333333, 114.66666667,
110.54, 107.82, 105.62000069, 79.79999821, 77.58666557, 75.78666928
), experimental_unit = c("A-1", "A-1", "A-1", "A-1", "A-2", "A-2",
"A-2", "A-2", "A-3", "A-3", "A-3", "A-3", "B-1", "B-1", "B-1",
"B-1", "B-2", "B-2", "B-2", "B-2", "B-3", "B-3", "B-3", "B-3"
)), row.names = c(NA, -24L), class = c("tbl_df", "tbl", "data.frame"
))
### Option 1 - Treat the experimental unit as a random effect since there are
### 4 repeat observations for the same unit
lme4::lmer(response ~ treatment + (1 | experimental_unit), data = tmp) %>%
emmeans::emmeans(., ~ treatment) %>%
as.data.frame()
#> treatment emmean SE df lower.CL upper.CL
#> 1 A 181.0794 10.83359 4 151.00058 211.1583
#> 2 B 101.9683 10.83359 4 71.88947 132.0472
#ggplot(.,aes(treatment, emmean)) +
#geom_pointrange(aes(ymin = lower.CL, ymax = upper.CL))
### Option 2 - instead of treating the unit as random effect, we average over the
### 4 repeat observations, and run a simple linear model
tmp %>%
group_by(experimental_unit) %>%
summarise(mean_response = mean(response)) %>%
mutate(treatment = c(rep("A", 3), rep("B", 3))) %>%
lm(mean_response ~ treatment, data = .) %>%
emmeans::emmeans(., ~ treatment) %>%
as.data.frame()
#> treatment emmean SE df lower.CL upper.CL
#> 1 A 181.0794 10.83359 4 151.00058 211.1583
#> 2 B 101.9683 10.83359 4 71.88947 132.0472
#ggplot(., aes(treatment, emmean)) +
#geom_pointrange(aes(ymin = lower.CL, ymax = upper.CL))
### Whether we include a random effect for the unit, or average over it and THEN model it, we find no difference in the
### marginal means for the treatments
### How do we incoporate the variation of the repeat measurments to the marginal means of the treatments?
### Do we then ignore the variation in the 'subsamples' and simply average over them PRIOR to modeling?
<sup>Created on 2021-07-31 by the [reprex package](https://reprex.tidyverse.org) (v2.0.0)</sup>
emmeans() does take into account the errors of random effects. This is what I get when I remove the complex sequences of pipes:
> mmod = lme4::lmer(response ~ treatment + (1 | experimental_unit), data = tmp)
> emmeans(mmod, "treatment")
treatment emmean SE df lower.CL upper.CL
A 181 10.8 4 151.0 211
B 102 10.8 4 71.9 132
Degrees-of-freedom method: kenward-roger
Confidence level used: 0.95
This is as shown. If I fit a fixed-effects model that accounts for experimental units as a fixed effect, I get:
> fmod = lm(response ~ treatment + experimental_unit, data = tmp)
> emmeans(fmod, "treatment")
NOTE: A nesting structure was detected in the fitted model:
experimental_unit %in% treatment
treatment emmean SE df lower.CL upper.CL
A 181 3.25 18 174.2 188
B 102 3.25 18 95.1 109
Results are averaged over the levels of: experimental_unit
Confidence level used: 0.95
The SEs of the latter results are considerably lower, and that is because the random variations in experimental_unit are modeled as fixed variations.
Apparently the piping you did accounts for the variation of the random effects and includes those in the EMMs. I think that is because you did things separately for each experimental unit and somehow combined those results. I'm not very comfortable with a sequence of pipes that is 7 steps long, and I don't understand why that results in just one set of means.
I recommend against the as.data.frame() at the end. That zaps out annotations that can be helpful in understanding what you have. If you are doing that to get more digits precision, I'll claim that those are digits you don't need, it just exaggerates the precision you are entitled to claim.
Notes on some follow-up comments
Subsequently, I am convinced that what we see in the piped operations in the second part of the OP doe indeed comprise computing the mean of each EU, then analyzing those.
Let's look at that in the context of the formal model. We have (sorry MathJax doesn't work on stackoverflow, but I'll leave the markup there anyway)
$$ Y_{ijk} = \mu + \tau_i + U_{ij} + E_{ijk} $$
where $Y_{ijk}$ is the kth response measurement on the ith treatment and jth EU in the ith treatment, and the rhs terms represent respectively the overall mean, the (fixed) treatment effects, the (random) EU effects, and the (random) error effects. We assume the random effects are all mutually independent. With a balanced design, the EMMs are just the marginal means:
$$ \bar Y_{i..} = \mu + \tau_i + \bar U_{i.} + \bar E_{i..} $$
where a '.' subscript means we averaged over that subscript. If there are n EUs per treatment and m measurements on each EU, we get that
$$ Var(\bar Y_{i..} = \sigma^2_U / n + \sigma^2_E / mn $$
Now, if we aggregate the data on EUs ahead of time, we are starting with
$$ \bar Y_{ij.} = \mu + U_{ij} + \bar E_{ij.} $$
However, if we then compute marginal means by averaging over j, we get exactly the same thing as we did before with $\bar Y_{i..}$, and the variance is exactly as already shown. That is why it doesn't matter if we aggregated first or not.

Matlab Code for Reading Text file with inconsistent rows

I am new to Matlab and have been working my way through using Google. But now I have hit the wall it seems.
I have a text file which looks like following:
Information is for illustration reasons only
Aggregated Results
Date;$/Val1;Total $;Exp. Val1;Act. Val1
01-Oct-2008; -5.20; -1717; 330; 323
02-Oct-2008; -1.79; -595; 333; 324
03-Oct-2008; -2.29; -765; 334; 321
04-Oct-2008; -2.74; -917; 335; 317
Total Period; -0.80; -8612; 10748; 10276
Aggregated Results for location State PA
Date;$/Val1;Total $;Exp. Val1;Act. Val1
01-Oct-2008; -5.20; -1717; 330; 323
02-Oct-2008; -1.79; -595; 333; 324
03-Oct-2008; -2.29; -765; 334; 321
Total Period; -0.80; -8612; 10748; 10276
Results for account A1
Date;$/Val1;Total $;Exp. Val1;Act. Val1
01-Oct-2008; -7.59; -372; 49; 51
Total Period; -0.84; -1262; 1502; 1431
Results for account A2
Date;$/MWh;Total $;Exp. MWh;Act. MWh
01-Oct-2008; -8.00; -392; 49; 51
02-Oct-2008; 0.96; 47; 49; 51
03-Oct-2008; -0.75; -37; 50; 48
04-Oct-2008; 1.28; 53; 41; 40
Total Period; -0.36; -534; 1502; 1431
I want to extract following information in a cell/matrix format so that I can use it later to selectively do operations like average of accounts A1 and A2 or average of PA and A1, etc.
PA -0.8
A1 -0.84
A2 -0.036
I'd go this way:
fid = fopen(filename,'r');
A = textscan(fid,'%s','delimiter','\r');
A = A{:};
str_i = 'Total Period';
ix = find(strncmp(A,str_i,length(str_i)));
res = arrayfun(#(i) str2num(A{ix(i)}(length(str_i)+2:end)),1:numel(ix),'UniformOutput',false);
res = cat(2,res{:});
This way you'll get all the numerical values after a string 'Total Period' in a matrix, so that you may pick the values you need.
Similarly you may operate with strings PA, A1 and A2.
Matlab is not that nice when it comes to dealing with messy data. You may want to preprocess it a bit first.
However, here is an easy general way to import mixed numeric and non-numeric data in Matlab for a limited number of normal sized files.
Step 1: Copy the contents of the file into excel and save it as xls or xlsx
Step 2: Use xlsread
[NUM,TXT,RAW]=xlsread('test.xlsx')
From there the parsing should be maneagable.
Hopefully they will add non-numeric support to csvread or dlmread in the future.

How can I searching for different variants of bioinformatics motifs in string, using Perl?

I have a program output with one tandem repeat in different variants. Is it possible to search (in a string) for the motif and to tell the program to find all variants with maximum "3" mismatches/insertions/deletions?
I will take a crack at this with the very limited information supplied.
First, a short friendly editorial:
<editorial>
Please learn how to ask a good question and how to be precise.
At a minimum, please:
Refrain from domain specific jargon such as "motif" and "tandem repeat" and "base pairs" without providing links or precise definitions;
Say what the goal is and what you have done so far;
Important: Provide clear examples of input and desired output.
It is not helpful to potential helpers on SO have to have to play 20 questions in comments to try and understand your question! I spent more time trying to figure out what you were asking than answering it.
</editorial>
The following program generates a string of 2 character pairs 5,428 pairs long in an array of 1,000 elements long. I realize it is more likely that you will be reading these from a file, but this is just an example. Obviously you would replace the random strings with your actual data from whatever source.
I do not know if 'AT','CG','TC','CA','TG','GC','GG' that I used are legitimate base pair combinations or not. (I slept through biology...) Just edit the map block pairs to legitimate pairs and change the 7 to the number of pairs if you want to generate legitimate random strings for testing.
If the substring at the offset point is 3 differences or less, the array element (a scalar value) is stored in an anonymous array in the value part of a hash. The key part of the hash is the substring that is a near match. Rather than array elements, the values could be file names, Perl data references or other relevant references you want to associate with your motif.
While I have just looked at character by character differences between the strings, you can put any specific logic that you need to look at by replacing the line foreach my $j (0..$#a1) { $diffs++ unless ($a1[$j] eq $a2[$j]); } with the comparison logic that works for your problem. I do not know how mismatches/insertions/deletions are represented in your string, so I leave that as an exercise to the reader. Perhaps Algorithm::Diff or String::Diff from CPAN?
It is easy to modify this program to have keyboard input for $target and $offset or have the string searched beginning to end rather than several strings at a fixed offset. Once again: it was not really clear what your goal is...
use strict; use warnings;
my #bps;
push(#bps,join('',map { ('AT','CG','TC','CA','TG','GC','GG')[rand 7] }
0..5428)) for(1..1_000);
my $len=length($bps[0]);
my $s_count= scalar #bps;
print "$s_count random strings generated $len characters long\n" ;
my $target="CGTCGCACAG";
my $offset=832;
my $nlen=length $target;
my %HoA;
my $diffs=0;
my #a2=split(//, $target);
substr($bps[-1], $offset, $nlen)=$target; #guarantee 1 match
substr($bps[-2], $offset, $nlen)="CATGGCACGG"; #anja example
foreach my $i (0..$#bps) {
my $cand=substr($bps[$i], $offset, $nlen);
my #a1=split(//, $cand);
$diffs=0;
foreach my $j (0..$#a1) { $diffs++ unless ($a1[$j] eq $a2[$j]); }
next if $diffs > 3;
push (#{$HoA{$cand}}, $i);
}
foreach my $hit (keys %HoA) {
my #a1=split(//, $hit);
$diffs=0;
my $ds="";
foreach my $j (0..$#a1) {
if($a1[$j] eq $a2[$j]) {
$ds.=" ";
} else {
$diffs++;
$ds.=$a1[$j];
}
}
print "Target: $target\n",
"Candidate: $hit\n",
"Differences: $ds $diffs differences\n",
"Array element: ";
foreach (#{$HoA{$hit}}) {
print "$_ " ;
}
print "\n\n";
}
Output:
1000 random strings generated 10858 characters long
Target: CGTCGCACAG
Candidate: CGTCGCACAG
Differences: 0 differences
Array element: 999
Target: CGTCGCACAG
Candidate: CGTCGCCGCG
Differences: CGC 3 differences
Array element: 696
Target: CGTCGCACAG
Candidate: CGTCGCCGAT
Differences: CG T 3 differences
Array element: 851
Target: CGTCGCACAG
Candidate: CGTCGCATGG
Differences: TG 2 differences
Array element: 986
Target: CGTCGCACAG
Candidate: CATGGCACGG
Differences: A G G 3 differences
Array element: 998
..several cut out..
Target: CGTCGCACAG
Candidate: CGTCGCTCCA
Differences: T CA 3 differences
Array element: 568 926
I believe that there are routines for this sort of thing in BioPerl.
In any case, you might get better answers if you asked this over at BioStar, the bioinformatics stack exchange.
When I was in my first couple years of learning perl, I wrote what I now consider to be a very inefficient (but functional) tandem repeat finder (which used to be available on my old job's company website) called tandyman. I wrote a fuzzy version of it a couple years later called cottonTandy. If I were to re-write it today, I would use hashes for a global search (given the allowed mistakes) and utilize pattern matching for a local search.
Here's an example of how you use it:
#!/usr/bin/perl
use Tandyman;
$sequence = "ATGCATCGTAGCGTTCAGTCGGCATCTATCTGACGTACTCTTACTGCATGAGTCTAGCTGTACTACGTACGAGCTGAGCAGCGTACgTG";
my $tandy = Tandyman->new(\$sequence,'n'); #Can't believe I coded it to take a scalar reference! Prob. fresh out of a cpp class when I wrote it.
$tandy->SetParams(4,2,3,3,4);
#The parameters are, in order:
# repeat unit size
# min number of repeat units to require a hit
# allowed mistakes per unit (an upper bound for "mistake concentration")
# allowed mistakes per window (a lower bound for "mistake concentration")
# number of units in a "window"
while(#repeat_info = $tandy->FindRepeat())
{print(join("\t",#repeat_info),"\n")}
The output of this test looks like this (and takes a horrendous 11 seconds to run):
25 32 TCTA 2 0.87 TCTA TCTG
58 72 CGTA 4 0.81 CTGTA CTA CGTA CGA
82 89 CGTA 2 0.87 CGTA CGTG
45 51 TGCA 2 0.87 TGCA TGA
65 72 ACGA 2 0.87 ACGT ACGA
23 29 CTAT 2 0.87 CAT CTAT
36 45 TACT 3 0.83 TACT CT TACT
24 31 ATCT 2 1 ATCT ATCT
51 59 AGCT 2 0.87 AGTCT AGCT
33 39 ACGT 2 0.87 ACGT ACT
62 72 ACGT 3 0.83 ACT ACGT ACGA
80 88 ACGT 2 0.87 AGCGT ACGT
81 88 GCGT 2 0.87 GCGT ACGT
63 70 CTAC 2 0.87 CTAC GTAC
32 38 GTAC 2 0.87 GAC GTAC
60 74 GTAC 4 0.81 GTAC TAC GTAC GAGC
23 30 CATC 2 0.87 CATC TATC
71 82 GAGC 3 0.83 GAGC TGAGC AGC
1 7 ATGC 2 0.87 ATGC ATC
54 60 CTAG 2 0.87 CTAG CTG
15 22 TCAG 2 0.87 TCAG TCGG
70 81 CGAG 3 0.83 CGAG CTGAG CAG
44 50 CATG 2 0.87 CTG CATG
25 32 TCTG 2 0.87 TCTA TCTG
82 89 CGTG 2 0.87 CGTA CGTG
55 73 TACG 5 0.75 TAGCTG TAC TACG TACG AG
69 83 AGCG 4 0.81 ACG AGCTG AGC AGCG
15 22 TCGG 2 0.87 TCAG TCGG
As you can see, it allows indels and SNPs. The columns are, in order:
Start position
Stop position
Consensus sequence
The number of units found
A quality metric out of 1
The repeat units separated by spaces
Note, that it's easy to supply parameters (as you can see from the output above) that will output junk/insignificant "repeats", but if you know how to supply good params, it can find what you set it upon finding.
Unfortunately, the package is not publicly available. I never bothered to make it available since it's so slow and not amenable to even prokaryotic-sized genome searches (though it would be workable for individual genes). In my novice coding days, I had started to add a feature to take a "state" as input so that I could run it on sections of a sequence in parallel and I never finished that once I learned hashes would make it so much faster. By that point, I had moved on to other projects. But if it would suit your needs, message me, I can email you a copy.
It's just shy of 1000 lines of code, but it has lots of bells & whistles, such as the allowance of IUPAC ambiguity codes (BDHVRYKMSWN). It works for both amino acids and nucleic acids. It filters out internal repeats (e.g. does not report TTTT or ATAT as 4nt consensuses).