WebAug 14, 2024 · How to Filter Rows in R Often you may be interested in subsetting a data frame based on certain conditions in R. Fortunately this is easy to do using the filter () function from the dplyr package. library (dplyr) This tutorial explains several examples of how to use this function in practice using the built-in dplyr dataset called starwars: WebYou can use brackets to select rows and columns from your dataframe. Selecting Rows debt[3:6, ] name payment 3 Dan 150 4 Rob 50 5 Rob 75 6 Rob 100 Here we selected rows 3 through 6 of debt. One thing to look at is the simplification that happens when you select a …
Did you know?
WebAug 31, 2011 · 6 Answers Sorted by: 67 t.first <- species [match (unique (species$Taxa), species$Taxa),] should give you what you're looking for. match returns indices of the first match in the compared vectors, which give you the rows you need. Share Improve this answer Follow answered Nov 13, 2013 at 3:04 alexwhan 15.5k 5 52 66 20 WebJun 5, 2024 · I need to filter out the rows where less than 50% (could be any percentage) of samples don't reach certain value, for example 1. Example Matrix: Tmtcars <- t (mtcars [1:5,c (2, 8:11)]) I need to select rows where at least 50% of cells are equal or greater than 1. Only the row “vs = c (0,0,1,1,0)” does not met this condition.
WebJul 28, 2024 · Output: prep str date 1 11 Welcome Sunday 2 12 to Monday Method 2: Using filter() with %in% operator. In this, first, pass your dataframe object to the filter function, then in the condition parameter write the column name in which you want to filter multiple values then put the %in% operator, and then pass a vector containing all the string … WebJan 25, 2024 · Method 1: Using filter () directly For this simply the conditions to check upon are passed to the filter function, this function automatically checks the dataframe and retrieves the rows which satisfy the conditions. Syntax: filter (df , condition) Parameter : df: The data frame object condition: filtering based upon this condition
WebSubset Data Frame and Matrix by Row Names in R (2 Examples) In this article, I’ll show how to select certain observations based on row names in the R programming language. The article contains the following content blocks: 1) Example 1: Extract Certain Data Frame Rows Based On Row Names. WebMar 3, 2024 · 4 Answers Sorted by: 2 Use b [i, ] to subset rows. b [i] subsets the elements of as.vector (b) indexed by i, which is not what you want. You don't need stringr to construct i, because base R has startsWith and grep. Either of these statements would work:
Web5 Answers. Sorted by: 72. For a data frame df, you can get df.new as: df.new = df [seq (1, nrow (df), 5), ] This creates an index from row 1 to nrow (number of rows of the table) every 5 rows. You can play with the starting point and the 5 to extract other sequences. Share.
WebIs there a way in R to select many non-consecutive i.e. odd or even rows/columns? I'm plotting the loadings for my Principal Components Analysis. I have 84 rows of data ordered like this: x_1 y_1... flights from gum to pvgWebIn this article, we will learn how to select a row or column from a matrix in R. The first way we can select a row or column is using the [] brackets. We can pass a row and a column in these brackets separate by a comma. For example, [1,2] … flights from gunsan to jejuWebDec 7, 2024 · You can use the following methods to filter the rows of a data.table in R: Method 1: Filter for Rows Based on One Condition dt [col1 == 'A', ] Method 2: Filter for Rows that Contain Value in List dt [col1 %in% c ('A', 'C'), ] Method 3: Filter for Rows where One of Several Conditions is Met dt [col1 == 'A' col2 < 10, ] flights from gunnedah to sydneyWebMay 23, 2024 · A row subset matrix can be extracted from the original matrix using a filter for the selected row names. Since a matrix’s elements are accessed in a dual index format, particular row selection can be carried out. Syntax: matrix [ vec , ] Where, vec contains the row names to be fetched All the columns are retrieved from the data frame. cherifer growthWebAug 5, 2014 · 2 Answers. You can use apply and all to check which rows have all elements > 10. big.mat <- matrix (rnorm (1000000, 20, 8), 1000, 1000) # Apply a function to each row of the matrix # (so we pass 1 to apply, 2 would be columns) # all returns TRUE if all of the element of the vector we pass # to it are TRUE good.lines <- apply (big.mat, 1 ... cherifer immunomax for kids reviewWebDec 1, 2024 · Zero out the diagonal and use apply (..., 1, any) to find the rows (and therefore also the columns owing to symmetry) which have values >= threshold. For testing, if cc is the matrix in the question then we have used cor (cc) and threshold = 0.6 instead because cc in the question is not a correlation matrix. flights from gulfport to san franciscoWebThe filter() function is used to subset a data frame, retaining all rows that satisfy your conditions. To be retained, the row must produce a value of TRUE for all conditions. Note that when a condition evaluates to NA the row will be dropped, unlike base subsetting with [. cherifer immunomax price in mercury