# LinReg linear regression u . nonlinear functions

with LINREG them is a useful application of the method of least squares are available - the description of a set of experimental data by a curve or a theoretical formula to obtain a linear or non - linear relationship which best fits the data - when possible small errors .

LinReg consists of the parts of the program :

• linear regression
• Nonlinear functions - straight - equations

applications:

Evaluation of measured values ​​and detecting the measured value characteristic

Calibration of measurement systems by linear regression

Detecting contexts within a series of studies

Representation of processes with linear or non- linear relation

Calculating a mathematical equation by y = ax + b or optionally for a non - linear relationship until 9 polynomial by:

Y = A0 + + a2x2 a1x + a3x3 ..... + amxm

Creating a formula from a value table

Examples : - Creation of characteristics for pumps

- Calibration curves for Photometry - polarimetry - AAS - etc.

- Preparation of performance curves for machines ,

graphical representation of curves with manual change possibility of coefficients

Creating a mathematical relation of graphic templates for acquisition

in computer programs

linear regression

calculations:

- Mathematical relationship of value pairs as a function of x by:

f ( x) = ax + ​​b for straight lines with and without intercept ( b = 0) possibility

calculating force with by 0/0

- Error for the slope and intercept .

- Error for each measured value in % and absolute.

- Correlation coefficient.

Graphical representation of the calculated function on the screen - at variable

Axis geometry

In order to optimize the calculation of additional pairs of values ​​can be appended , deleted or changed .

non-linear functions

For the presentation of functions and technical processes with mathematical operations in a non-linear curve.

Creating a formula from a value table with nonlinear history

Detection of operations with non-linear character

Applications:

- Creation of curves or absorption curves

- Performance curves for machines

- Forming Calculations n in a degree function.

For a number of measurements a mathematical function is calculated to 9 polynomial.

Graphical representation of the calculated function on the screen

Line equations

manual drawing straight in the coordinate system

Target of slope + intercept or 2 points

Calculation of intersection, intersection angles, axle breakdown

Representation of parabolas with X / Y symmetry and form Y = ax² + bx + c