R Vectorizing Operation

R Vectorizing Operation

Content Index :

R Vectorizing Operation
Tag : r , By : Paulh
Date : November 27 2020, 04:01 AM

this will help The second part needs to be done with outer. You can use a^b in a vectorized way, but it will not apply the operation to the first element of a vs all elements of b, the the second element of a vs all elements of b, etc., like you want in this case. It will just give c(a[1]^b[1], a[2]^b[2], ..., a[n]^b[n]).
out_vec2 <- rowSums(df[5:100] * outer(1 + abs(df$X1)/100, -(0:95)/12, `^`))

all.equal(out_vec, out_vec2)
# [1] TRUE
loop <- function(){
  out_vec <- c()
  for (i in 1:nrow(df)) {
    out_vec[i]<- sum(df[i, 5:100] * (1 + abs(df$X1[i])/100) ^ -(0:95 / 12))

vect <- function() rowSums(df[5:100] * outer(1 + abs(df$X1)/100, -(0:95)/12, `^`))

microbenchmark(loop(), vect(), times = 10)
# Unit: milliseconds
#    expr         min          lq        mean      median          uq        max neval
#  loop() 12065.34780 12756.12062 13095.97435 12892.87818 13460.56978 15030.0197    10
#  vect()    35.73011    41.36212    60.57327    54.40029    79.25182   104.0453    10

No Comments Right Now !

Boards Message :
You Must Login Or Sign Up to Add Your Comments .

Share : facebook icon twitter icon

R - vectorizing a which operation

Tag : r , By : Hugo
Date : March 29 2020, 07:55 AM
hop of those help? Hi I have a function in R that I'm trying to optimize for performance. I need to vectorize a for loop. My problem is the slightly convoluted data structure and the way I need to perform lookups using the 'which' command. , You could write your function like this:
foo <- function(AA, BB, CC) {
  pa <- AA*CC
  x <- outer(pa, pa)
  diag(x) <- 0
  res <- colSums(x)*BB

Vectorizing this non-unique-key operation

Tag : python , By : Sigtryggur
Date : March 29 2020, 07:55 AM
may help you . Here's a vectorized approach based upon searchsorted -
# Get sorted index positions
idx = np.searchsorted(rows, test)

# Set out-of-bounds(invalid ones) to some dummy index, say 0
idx[idx==len(rows)] = 0

# Get invalid mask array found out by indexing data array
# with those indices and looking for matches
invalid_mask = rows[idx] != test

# Get data indexed array as output and set invalid places with 0s
out = data[idx]
out[invalid_mask] = 0
out = data[idx] * (rows[idx] == test) # skips using `invalid_mask`

out = np.where(invalid_mask, 0, data[idx])

Vectorizing a for-loop operation

Tag : matlab , By : Alecsandru Soare
Date : March 29 2020, 07:55 AM
it should still fix some issue That's pretty simple, especially since j is only used for row indexing here:
X(:,1)= random1;
for i = 1:length(Time)
    X(:,i+1) = X(:,i) - mu*X(:,i)*TimeStep + Sigma*sqrt(2*mu)*sqrt(TimeStep)*random2(i);

Vectorizing list of lists operation in R

Tag : r , By : Cube_Zombie
Date : March 29 2020, 07:55 AM

Vectorizing operation in NumPy

Tag : python , By : user98986
Date : March 29 2020, 07:55 AM
Related Posts Related QUESTIONS :
  • R programming: creating a stacked bar graph, with variable colors for each stacked bar
  • How to identify all columns that contain binary representation
  • Filter different groups by different factor levels
  • Saving .xlsx file to disc, form http post request
  • Add an "all" option under the filter that selects the number of rows displayed in a datatable
  • How to select second column of every xts in list
  • Generate a frequency dataframe out of an input dataframe
  • Why manual autocorrelation does not match acf() results?
  • Merge 3 dataframes which are different to each other
  • remove adjacent duplicates from string
  • How to change the position of stacked stacked bar chart in ggplot in R?
  • How to divide each of a range a variables by a second range of variables in R
  • Why do I need to assemble vector before scaling in Spark?
  • How to select individuals which appear in multiple groups?
  • How can I fill columns based on values in another column?
  • 32 bit R and 64 bit R: output differs
  • Remove a single backslash in paste0 output
  • ggplot2 different label for the first break
  • TSP in R, with given distances
  • How to find the given value from the range of values?
  • Solution on R group by issue _ multiple combination
  • Transform multiple columns with a function that uses different arguments per column
  • How can I parse a string with the format "1/16/2019 1:24:51" into a POSIXct or other date variable?
  • How to plot a box plot in R for outlier detection for a huge number of rows?
  • How to change column name according to another dataframe in R?
  • `sjPlot::tab_df()`--how to set the number of decimal places?
  • time average for specific time range in r
  • joining dataframes by closest time and another key in r
  • How to create nested for loop for a certain range
  • New category based on sequence of date ranges
  • how to extract formula from coxph model summary in R?
  • add row based on variable condition in R
  • Generating the sequence 111122222333334
  • Unable to use has_goog_key() in R
  • how to multiply each row with a scaler in corresponding column?
  • R is not recognizing levels of a factor as the same. Is there a way to do this?
  • Calculating mean of replicate experiment result values in a column based on multiple columns using R
  • Best method to extract the first instance of a string between specified keywords using data.table
  • ignore optional combination of alphanumeric characters in str_extract
  • Why tracemem shows two copies when modification occurs inside function body?
  • Can't use mppm on multitype point patterns
  • How to move selected matrix rows to top of matrix based on a selection vector of row names
  • Combining expressions with a common operator
  • Passing string through multiple filters for matching
  • Convert two columns in R to rows of unique occurrence
  • How to create a dataframe using a function based on user-input?
  • How to access the visited vertices in a given shortest path using R igraph
  • Differences in Unicode character output with print()
  • Extracting Function or Objects from a String and then Piping Them with Magrittr/Dplyr
  • renderUI not evaluated until it is rendered
  • Find the maximum absolute value by row in an R data frame
  • Extracting data from irregular lists using purrr:map()
  • transforming data based on range of column in r
  • Identify and subset rows with some similar information
  • converting character from mongolite to timestamp in R
  • Create list from two vectors with every combo of each
  • Error in running a spread because of unique 'key combinations'; combining rows of data
  • visualize numerical strings as a matrixed heatmap
  • how to make a blocked matrix?
  • How to summarize with two functions using with dplyr
  • shadow
    Privacy Policy - Terms - Contact Us © scrbit.com