sum_up
computes the sum up value for each sample (row) of a
multi-channel signal.
sum_up(df, axes = NULL)
dataframe. multi-channel signal, with the first column being the timestamp in POSXct format.
numerical vector. Specify the column indices for each axis. When
this value is NULL, the function assumes the axes are starting from column
2 to the end. Default is NULL
.
dataframe. The transformed dataframe will have the same number of rows as input dataframe but only two columns, with the first being timestamps and second being the sum up values.
This function takes a dataframe of a multi-channel signal as input, and then computes the sum of each row and returns a transformed dataframe with two columns.
This function is used to
combine MIMS-unit values on each axis into a single value after aggregating
over each epoch using aggregate_for_mims
.
Other transformation functions:
compute_orientation()
,
vector_magnitude()
# Use the first 10 rows of the sample data as an example
df = sample_raw_accel_data[1:10,]
df
#> HEADER_TIME_STAMP X Y Z
#> 1 2016-01-15 11:00:00 0.148 -0.438 0.016
#> 2 2016-01-15 11:00:00 0.215 -0.418 -0.023
#> 3 2016-01-15 11:00:00 0.266 -0.402 -0.012
#> 4 2016-01-15 11:00:00 0.336 -0.430 0.012
#> 5 2016-01-15 11:00:00 0.430 -0.320 0.000
#> 6 2016-01-15 11:00:00 0.535 -0.258 0.004
#> 7 2016-01-15 11:00:00 0.641 -0.348 0.020
#> 8 2016-01-15 11:00:00 0.777 -0.418 0.023
#> 9 2016-01-15 11:00:00 0.938 -0.359 0.043
#> 10 2016-01-15 11:00:00 1.113 -0.234 0.055
# By default, the function will assume columns starting from 2 to be axial
# values.
sum_up(df)
#> HEADER_TIME_STAMP SUMUP_X_Y_Z
#> 1 2016-01-15 11:00:00 -0.274
#> 2 2016-01-15 11:00:00 -0.226
#> 3 2016-01-15 11:00:00 -0.148
#> 4 2016-01-15 11:00:00 -0.082
#> 5 2016-01-15 11:00:00 0.110
#> 6 2016-01-15 11:00:00 0.281
#> 7 2016-01-15 11:00:00 0.313
#> 8 2016-01-15 11:00:00 0.382
#> 9 2016-01-15 11:00:00 0.622
#> 10 2016-01-15 11:00:00 0.934
# Or, you may specify the column indices yourself
sum_up(df, axes=c(2,3,4))
#> HEADER_TIME_STAMP SUMUP_X_Y_Z
#> 1 2016-01-15 11:00:00 -0.274
#> 2 2016-01-15 11:00:00 -0.226
#> 3 2016-01-15 11:00:00 -0.148
#> 4 2016-01-15 11:00:00 -0.082
#> 5 2016-01-15 11:00:00 0.110
#> 6 2016-01-15 11:00:00 0.281
#> 7 2016-01-15 11:00:00 0.313
#> 8 2016-01-15 11:00:00 0.382
#> 9 2016-01-15 11:00:00 0.622
#> 10 2016-01-15 11:00:00 0.934
# Or, if you only want to consider x and y axes
sum_up(df, axes=c(2,3))
#> HEADER_TIME_STAMP SUMUP_X_Y
#> 1 2016-01-15 11:00:00 -0.290
#> 2 2016-01-15 11:00:00 -0.203
#> 3 2016-01-15 11:00:00 -0.136
#> 4 2016-01-15 11:00:00 -0.094
#> 5 2016-01-15 11:00:00 0.110
#> 6 2016-01-15 11:00:00 0.277
#> 7 2016-01-15 11:00:00 0.293
#> 8 2016-01-15 11:00:00 0.359
#> 9 2016-01-15 11:00:00 0.579
#> 10 2016-01-15 11:00:00 0.879
# Or, just return the chosen column
sum_up(df, axes=c(2))
#> HEADER_TIME_STAMP SUMUP_X
#> 1 2016-01-15 11:00:00 0.148
#> 2 2016-01-15 11:00:00 0.215
#> 3 2016-01-15 11:00:00 0.266
#> 4 2016-01-15 11:00:00 0.336
#> 5 2016-01-15 11:00:00 0.430
#> 6 2016-01-15 11:00:00 0.535
#> 7 2016-01-15 11:00:00 0.641
#> 8 2016-01-15 11:00:00 0.777
#> 9 2016-01-15 11:00:00 0.938
#> 10 2016-01-15 11:00:00 1.113