Engineering Computing 212
Midterm

Chapter 1 – LabView Basics

Front Panel Toolbar
-Run/Broken Run
- Continuous Run
- Abort Execution
- Pause/Continue
- Font Ring
- Alignment Ring

Block Diagram Toolbar
- Highlight Execution
- Step into
- Step over
- Step out
- Warning Indicator

Palettes

1. Tools – operate and modify both front panel and block diagram
2. Controls – located on the front panel
3. Functions – located on the block diagram

Chapter 2 – VI Main Component

Block Diagram Features - control terminal (thick border) - indicator terminal (thin border)

Data Flow Programming - block diagram does NOT execute left to right. - nodes execute when data is available to all inputs

Block Diagram Colors

1. Number – Orange 2. Boolean – Green 3. Integer – Blue 4. String – Pink

Wires

1. Scalar – Thin 2. 1D Array – Thick 3. 2D Array – Double

Chapter 3, 4 , 5 – MatLab Basics Matrices

Array - A= [ 2 , 4 , 5 ; 3 , 16 , 7] ;

Array operations (element by element)

1. Scalar – Array Addition A+b 2. Scalar – Array Subtraction A-b 3. Scalar – Array Multiplication A.*B 4. Scalar – Array Division A./B

Polynomial Functions > roots(x) roots of a polynomial >poly(x) coefficient of a polynomial whose roots are specified by the array x. > polyval(a,x) evaluates a polynomial at specified values of its independent variable x

Format Command > format short – 4 digits after decimal > format long – 14 digits after decimal > format short e > 5 digits plus exponent > format long e > 16 digits plus exponent > format bank > 2 decimal digits > format rat > approximate ratio

X-Y Plotting

> plot(x,y) – plots any pair of vectors x and y versus eachother (vectors must be same length)

Multiple X-Y plots

> plot(x,y,u,v) – plots 4 arrays (x vs. y) & (u vs. v)

Plotting Polynomials

> plot(x, polyval(a,x)) – plots the polynomial at specified values of the independent Variable

Specialized Plot Commands > bar(x,y) – bar chart > polar(theta, r) – polar plot > stair (x,y) – stairs plot >stem(x,y) – stem plot

Subplots > subplot (m,n,p) – displays several plots in the same window - m=rows - n=columns - p=pane position for next plot

Label, Title and Legend Commands > x label (‘string’) > y label (‘string’) > title (‘string’) > legend (‘str1’ , ‘str2’)

Stream (text) modifiers for plotting > \bf – boldface > \it – italics > fontname{fontname} > fontsize{fontsize} > _{xxx} – subscripts > ^{xxx} – superscripts >\rm – restore font

Chapter 4 – Editting and Debugging

Editing techniques > selecting > moving > deleting > resizing > labeling > coloring

Debugging Techniques > finding errors > highlight execution > breakpoints > probes

Chapter 5 – SubVI’s

Icon/Connector >representation of the SubVI >terminals that correspond to the controls and indictators > an icon represents a VI in other block diagrams > A connector shows available terminals for data transfer

Create SubVI

Hierarchy Window >Shows structure of all Vis > Shows dependencies

Chapter 6 – LabView Structures

For Loop > Runs/executes code inside border > Number of specified iterations

While Loop >Runs code inside border until a condition is met >True/false condition

Shift Register >Transfers values from one iteration to the next

Case structure >Executes conditional text > Text can be Boolean, numeric or string

Sequence Structure >Executes sub-diagrams sequentially

Formula node >Always programming of one or more algebraic formulas

Chapter 7 – LabView Arrays and Clusters

Arrays
Creating Arrays
1. place array shell on front panel
2. put data objects inside shell

Initialize Array
>creates n-dimensional array with elements containing a specified values.
Elements are the same value.

Build Array >assembles multiple arrays or adds scalar elements to an array

Array Subset >returns a portion of an array

Polymorphism >arithmetic functions accept inputs of different dimensions >outputs will be the size of the smaller array

Clusters
Creating Clusters
1. place cluster shell on front panel
2. place mixed type data objects inside shell

Chapter 8 – LabView Charts and Graphs

Graph: displays pre-generated arrays of data

Chart: displays data by appending new data as it becomes available

Waveform Chart: - Strip chart: plot moves to left as new data is added to right

- Scope chart: plot is erased when data points reach right border of the chart

- Sweep chart: moving vertical line marks the beginning of new data

Express VI’s

Express VI’S: interactive VI’s with a configurable dialog

Standard VI’s : modularized VI’s customized by wiring