Questions tagged [downsampling]
231 questions
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How do I downsample a Pandas dataframe linearly to another column set?
How do I down-sample (linearly) one dataframe (counts at some distribution of diameters, logged at the lower bound, so the first entry is 0 counts between 296.54 and 303.14 nm, the second entry is 1 count between 303.14 and 311.88 nm etc).
296.54…
bernski
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2 answers
Resampling timestamps in a CSV
I have a CSV file that stores data from different smartphone sensors. The timestamps are elapsed nanoseconds since the program to record the data was started. Short…
lapplapp
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2 answers
Aggregation of time-series data on multiple columns
rand_val new_val copy_time
2020-10-15 00:00:00 7 26 2020-10-15 00:00:00
2020-10-15 00:00:10 8 29 2020-10-15 00:00:10
2020-10-15 00:00:20 1 53 2020-10-15 00:00:20
2020-10-15…
Borut Flis
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Downsampling signal in frequency domain
Is known that the convolution in time domain is equal to the element wise of the FFT's of input and filter.
The time scalling property says that:
So, my question is: Can I apply downsampling (strides > 1 in convolutional network) in frequency…
Diego Ruiz
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1 answer
Image/2D array resampling in C
I am looking to implement a resampling algorithm for a 2D array(it could be grayscale image or some 2D array of floating point values).
The steps involved in this particular operation are:
Given a 2D array, I first downsample it to size of 8x8 or…
goldenmean
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Why VoxelGrid after filtering gives me only 1 point in the cloud?
I am receiving ROS message of type
sensor_msgs::PointCloud2ConstPtr
in my callback function then I transform it to pointer of type
pcl::PointCloud::Ptr
using function
pcl::fromROSMsg.
After that using this code from pcl tutorials…
LBajlo
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1 answer
InfluxDB - Keep timestamp of record on downsampling
InfluxDB version used: 1.8.0
Given a time series db that is used for storing e.g. temperatures from iot sensors (on different locations).
The sensors are queried e.g. every other minute.
Now the maximum temperature per sensor for the last hour can…
CyclingSir
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1 answer
downsampling gps data using haversine formula using python
I have a high frequency of gps data which i want to downsample to every 50 meters ie keep gps latitude and longitude every 50 meter and discard inbetween points. I found a python code on the internet which basically calculates the distance between…
codeheadache
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1 answer
numpy 1-D array size reduction without losing the signature of the plot
In order to increase the computational speed, i need to resize the 1-D numpy array . The caveat here is that the numpy array is to be used as a shape descriptive curve which will further be utilized as a tool to classify the different class.
…
Saibala Sundram
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Downsample Timestamp in milisecond range in Postgres
I have a table as below
timestamp v1 v2 v3
2020/01/01 08:10:20.300 10 20 30
2020/01/01 08:10:20.306 11 21 31
2020/01/01 08:10:20.310 12 22 32
2020/01/01 08:10:20.318 13 23 …
codeheadache
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files crash after i try to downsample them with scipy
I have a wav of the following youtube video: https://www.youtube.com/watch?v=glOnDceqqJc
which has 44100Hrz and has the length of 2 minutes and I want to downsample it to 16000Hrz
my script works on shorter files but when I run my script with this…
Michael Ben Haym
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0 answers
Weights in BCEWithLogitsLoss
I am facing an issue in a multi label, multi class classification task. I have a dataset of size 33000, each samples containing 104 classes. I split the dataset in 16500 samples with labels such as [1, 0, 1, 0, 0, …], [0, 1, 1, 0, 1, …], [1, 0, 0,…
Mougart
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Downsampling problems with complex dataset
I have an imbalanced dataset and I want to downsample it.
This is the dataset:
testframe = pd.DataFrame()
testframe['id_unique'] = [0,0,0,1,1,1,2,2,2,3,3,3]
testframe['t'] = [1,2,3,1,2,3,1,2,3,1,2,3]
testframe['value'] =…
nopact
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1 answer
Resample timeseries with panda
i have to downsample the following time series with panda:
Time ch1 ,ch2 ,ch3 ,ch4
09/19/2019 22:00:00.000000000 ,0 ,0 ,8675601 ,0
09/19/2019 22:00:00.000976562 ,8028645 ,0 ,8662525…
HunterDev
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1
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1 answer
Is it possible to increase the sampling rate of ADXL345 on a Raspberry Pi with Python?
I have a Raspberry Pi with 2 ADXL345 accelerometers, and I want to maximize the data sampling rate from them both. As I was searching the internet, I became intrigued to find someone on the Raspberry Pi forum…
S. R. Colledge
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