Linear Interpolation made easy

Saad Iqbal | 🗓️Modified: January 3, 2014 | ⏳Read Time: 7 min | 👁Post Views: 563
Linear Interpolation is a very efficient and useful technique to get a required data from a limited source of data. In Civil Engineering we have to deal with a lot of calculations like minimum thickness table in Reinforced concrete structures, in Structural Number Calculation in Transportation engineering and so many.

linear interpolation calculation tool

Linear interpolation is a technique of curve fitting in which if a straight line is faced, one can easy find the various points on that line.

What is Interpolation

This tool is provided specially for civil engineers, to help them in their estimation work and in the various civil engineering calculation.

Linear Interpolation Calculation

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Enter the Coordinates of First Points: X1 Y1
Enter the Coordinates of Second Point: X2 Y2
Enter the point whose value is required: X
Round the answer YesNo
Interpolated value: Y

How to Use this tool

It is very easy to use this tool, the value which you need assume it by a variable X and let us say its corresponding required value is Y. The values from which a straight line is made, assume it having names X1, Y1 and X2, Y2 as the coordinates.

This tool has a special feature of rounding it off. If you wants to round off then set this option as yes, otherwise set this option as No.

Examples of calculation

let us say we need load damaging factor for design of flexible pavement in transportation engineering where structural number is 3.65 so it comes between 3.60 and 3.70 where load of single axle is 9 k. load damaging factor for 3.60 is 0.0345 and for 3.70 is 0.0225 thus for for SN of 3.65 is 0.0285 as shown in the figure.

linear interpolation calculation example

Editorial Remarks:

The use of this table is under terms of use under privacy section of iamcivilengineer.com. The result or any loss or damage done by using this tool, iamcivilengineer.com would not be responsible. so be cautious in your calculation.

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Keywords for Interpolation Tool

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