Local extrema based data sampling system

Patent metadata

Field	Value
Publication number	US-2017004137-A1
Application number	US-201514957826-A
Country	US
Kind code	A1
Filing date	Dec 3, 2015
Priority date	Jul 3, 2015
Publication date	Jan 5, 2017
Grant date	—

Abstract

A computing device sorts a plurality of data points in a first dimension. A first data point has a first value, a second data point has a second value, and a third data point has a third value defined in a second dimension. (a) The second value is compared to the first and third values. (b) When the second value is less than the first value and greater than the third value, or the second value is greater than the first value and less than the third value, the data point is deleted. (c) The first data point is defined as the second data point. (d) The second data point is defined as the third data point. (e) The third data point is defined as a next data point. (a)-(e) are repeated until each of the plurality of data points is defined as the third data point to define a plurality of sampled data points as remaining data points of the plurality of data points.

First claim

1 . A non-transitory computer-readable medium having stored thereon computer-readable instructions that when executed by a computing device cause the computing device to:
read a plurality of data points from a dataset, wherein each data point of the plurality of data points is defined in a first dimension and a second dimension, wherein the plurality of data points are sorted in the first dimension; (a) define a first data point from the read plurality of data points, wherein the first data point has a first value (V 1y ) defined in the second dimension; (b) define a second data point from the read plurality of data points, wherein the second data point has a second value (V 2y ) defined in the second dimension; (c) define a third data point from the read plurality of data points, wherein the third data point has a third value (V 3y ) defined in the second dimension; (d) determine whether the second data point is a local minima or a local maxima, wherein the second data point is the local minima when V 2y <V 1y and V 2y <V 3y , and wherein the second data point is the local maxima when V 2y >V 1y and V 2y >V 3y ; (e) when the second data point is neither the local maxima nor the local minima based on the determination, delete the second data point from the read plurality of data points; (f) define the first data point as the second data point and V 1y =V 2y ; (g) define the second data point as the third data point and V 2y =V 3y ; (h) define the third data point as a next data point from the read plurality of data points and V 3y =a value of the next data point defined in the second dimension; (i) repeat (d)-(h) until each of the read plurality of data points is defined as the third data point to define a plurality of sampled data points as remaining data points of the read plurality of data points; and store the defined plurality of sampled data points to the non-transitory computer-readable medium for rendering a graph with the stored plurality of sampled data points.

2 . The non-transitory computer-readable medium of claim 1 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device to render the graph on a display with the stored plurality of sampled data points.

3 . The non-transitory computer-readable medium of claim 1 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device to:
receive a request to sample the plurality of data points from the dataset from a second computing device before reading the plurality of data points from the dataset; and send the stored plurality of sampled data points to the second computing device.

4 . The non-transitory computer-readable medium of claim 1 , wherein the dataset is read from a second computing device.

5 . The non-transitory computer-readable medium of claim 1 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device, before (a), to:
create a number of threads executing on the computing device; divide the read plurality of data points into data point subsets based on the number of threads; and associate each data point subset of the data point subsets with a different created thread, wherein (a)-(i) is performed by each created thread, wherein the read plurality of data points is the data point subset of the associated, different created thread.

6 . The non-transitory computer-readable medium of claim 5 , wherein the read plurality of data points is divided approximately equally.

7 . The non-transitory computer-readable medium of claim 2 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device to:
compute a first range value in the first dimension based on a minimum value in the first dimension and a maximum value in the first dimension; compute a second range value in the second dimension based on a minimum value in the second dimension and a maximum value in the second dimension; compute a first conversion value in the first dimension based on a first display window size in the first dimension; compute a second conversion value in the second dimension based on a second display window size in the second dimension; convert each first dimension value of the read plurality of data points to fit within the first display window size using the determined first conversion value; and convert each second dimension value of the read plurality of data points to fit within the second display window size using the determined second conversion value, wherein the graph is rendered on the display with the converted first dimension value and the converted second dimension value.

8 . The non-transitory computer-readable medium of claim 7 , wherein the first conversion value is equal to (W/Range x ) and the second conversion value is equal to (H/Range y ), where W is the first display window size, Range x is the computed first range value, H is the second display window size, and Range y is the computed second range value.

9 . The non-transitory computer-readable medium of claim 8 , wherein each first dimension value is converted using (W/Range x )*(Read x −Min x ) and each second dimension value is converted using (H/Range y )*(Read y −Min y ), where Read x is a respective first dimension value, Min x is the minimum value in the first dimension, Read y is a respective second dimension value, and Min y is the minimum value in the second dimension.

10 . The non-transitory computer-readable medium of claim 7 , wherein the converting each first dimension value and the converting each second dimension value are performed after (i) on the defined plurality of sampled data points.

11 . The non-transitory computer-readable medium of claim 7 , wherein the converting each first dimension value and the converting each second dimension value is performed after (c) and before (d).

12 . The non-transitory computer-readable medium of claim 7 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device to receive the first display window size and the second display window size from a second computing device, wherein the graph is rendered on the display by the second computing device.

13 . The non-transitory computer-readable medium of claim 1 , further comprising computer-readable instructions that, when executed by the computing device, cause the computing device to:
before (j), compute a partition end value as a sum of a first value defined in the first dimension of the defined first data point and a partition width value in the first dimension; (j) before (d), compare a second value defined in the first dimension of the defined third data point to the computed partition end value; (k) when the second value defined in the first dimension is less than the computed partition end value, perform (d)-(i), wherein (i) further comprises repeating (j) and (k) while the second value defined in the first dimension is less than the computed partition end value; and when the second value defined in the first dimension is greater than or equal to the computed partition end value, (l) update the computed partition end value by adding the partition width value in the first dimension; (m) define the first data point as the third data point and V 1y =V 3y ; (n) define the second data point as a data point after the third data point from the read plurality of data points when the third data point is not a last data point of the read plurality of data points and V 2y =a value of the d

Assignees

• Sas Inst Inc

Inventors

• Raina Vineet
• Daga Swapnil

Classifications

• G06T3/40

  Scaling of whole images or parts thereof, e.g. expanding or contracting · CPC title

• G06F7/535

  Dividing only · CPC title

• G06T11/26

  Drawing of charts or graphs · CPC title

• G06F16/284

  Relational databases · CPC title

• G06F16/252 Primary

  between a Database Management System and a front-end application · CPC title