how to deploy sensor nodes randomly in a matrix 100x100

how to deploy sensor nodes randomly in a matrix 100x100 ?

Answer 1

[Jan]

M        = zeros(100, 100);
Index    = randperm(100*100, 100);   % Linear index
M(Index) = 1;

Now you have 100 ones in a zero matrix. If "deploy nodes in a matrix" means something else, please be so kind and explain the details.

[Debalina Pal]

how can I plot this in a 100x100 matrix?and I want to show this using a figure and I want to deploy 1000 sensor nodes within this matrix and among those sensor nodes , some nodes are malicious(that means ,sends wrong information to the cluster head nodes/base station) and the malicious nodes are shown in red color and normal nodes are shown in blue.

[Jan]

Please provide some example data. Otherwise it is hard to post a matching code. It matters how your data are stored. There are a lot of different methods to visualize these data: As points, a mesh, a patch, circles, spheres, ...

[Debalina Pal]

Here I am attaching my CSV file and sample picture of my project concept.Actually,my project is to measure the uncertainty of the fused information using Bayesian inference and Dempster Shafer Theory.In case of Bayesian Inference Prior Probability is provided from the CSV data set. Kindly help me.If you want I'll provide a sample paper of Bayesian Inference and Dempster Shafer Theory.And Thank you in advance.

[Walter Roberson]

You have been providing temperature data for your several questions on this topic, but none of us have been able to understand how temperature data over various months of the years has anything to do with wireless sensor networks ??

[Jan]

@Debalina Pal: I do not see, how this picture is related to the question. The CSV file does not clarify also, how you want to visualize the data. Remember that "uncertainty of the fused information using Bayesian inference and Dempster Shafer Theory" is an extremely specific topic and most of the members of the forum will not have an idea of what this is. But your problem is only to draw some points on a kind of grid, as far as I understand. Then the best explanation would be something like:

 My inputs are:

x = [1, 4, 17, 32]
y = [8, 19, 7, 99]

 I want to draw a 100x100 grid/checkerboard/mesh/??? and set
 points/circles/fill patches/??? on the given x and y positions.

This would allow to suggest a solution, but providing the paper would not. It is your decision how you want to display the values and this cannot be found in the paper of someone else.

[Debalina Pal]

Thanks a lot to identify my actual doubts.Actually I'm little bit confused about this.In the Bayesian inference I need mean and variance which is taken from prior probability.Then from where I can get these values?Kindly help me and please if u can understand the situation.I'm really confused about that portion.

[Walter Roberson]

Hmmm -- is it possible that you have one of these .csv files per node ?

[Debalina Pal]

not at all..then how should I do this project?please help me.My assignment is to fused information and measure the uncertainty of that fused information using bayesian inference and dempster shafer theory.Actually I have to compare both this techniques.How could I do this?And the structure is just like the previous sample picture.I'm attaching it again.

[Debalina Pal]

Till now,I didn't get any answers. At least tell me how can I apply Bayesian Inference and Dempster Shafer Theory in this scenario.Please help me. At least suggest something that can help me.

[Walter Roberson]

You cannot apply those techniques in this scenario. To fuse information, you need multiple measurements of the same information to be considered for reliability and weighed, but you do not have that: you have a time series of data for a single location. Notice that the diagram shows multiple cluster head nodes ("that are changing in each round") you have at most one unchanging node.

[Debalina Pal]

Changing of cluster head nodes are not mandatory.Its because only,if a node become cluster head node again and again then that node consume more and more energy than the other nodes present in that cluster.That's why I wrote there that the cluster head nodes will change in each round nothing else. And My work is to measure only the uncertainty from the fused information.

[Debalina Pal]

If the changing of cluster head is not mandatory,after that still is it not possible?

[Walter Roberson]

You do not have a cluster: you have one node. You need at least two competing measurements for the same data to consider fusing.

... What is this data? If those temperatures are Celsius then they look like they would have to be of a location a little north of Barbados.

[Debalina Pal]

yes I have clusters and I want to fuse temperature data which are in celsius. "they would have to be of a location a little north of Barbados." exactly the concept is just like this.Suppose,India is a Country.And consider the north part is a cluster,the south part is a cluster and east and west part also are the clusters. Here I am attaching a Paper to clear the concept.But in this paper there are three types of parameters that's why the combiner is used.But I take only one parameter and that is temperature data in Celsius.

[Walter Roberson]

"yes I have clusters"

I asked, "is it possible that you have one of these .csv files per node ?" and you said "not at all". Your description of your clusters gives no indication that you have multiple measurements of the same underlying data: you have timeseries measurements of different measurements at best.

It is not meaningful to talk about the reliability of the exact maximum and minimum temperature measurements by comparing single readings from different parts of a country against each other. Not even in tiny Liechtenstein, which has mountains in it. In the city I live in, there are two weather official weather stations, one downtown and one at the airport, 10 km away, and the two routinely have different readings (downtown is at the meeting of two important rivers.) It is true that you could probably get away with four stations for Vatican City (less than 1/2 square km), and possibly Monaco (2 square km), but by the time you get to Nauru (21 square km) then placement starts to matter, as the temperature varies across the island. Hmmm -- Nauru might be just about right, if you put stations at the cardinal points, then there might be enough overlap in effective area that you could use two adjacent readings to "sanity check" any one reading.

[Debalina Pal]

If there is more than one parameter i.e. temperature,rainfall and humidity which are collected from different sensors and fuse data which are collected from these different sensors,then bayesian inference and dempster shafer is possible to achieve better accuracy and robustness of the information required for high level weather assesment ?

[Debalina Pal]

Is it possible?please reply

[Walter Roberson]

If you had multiple sensors of the same kind for the same area, then you could potentially do fusion.

If you had multiple different sensors for an area, but not at least two of the same kind of sensor, then any fusion that could be done would be crude, such as detecting an improbable freezing rain http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cld/prcp/zr/fcst/fcst.rxml in that freezing rain requires a low pressure near the ground and becomes increasingly unlikely as it gets colder (but see also https://www.weatherlogics.com/freezing-rain-vs-freezing-drizzle-whats-the-difference-2/)

[Debalina Pal]

Thanks a lot for helping me like this.This helps me to clear my doubts.Thank you so much. Now my question is : If We deploy different types sensor nodes in a certain area. These sensors can sense Temperature, Precipitation, Wind speed of that certain area. These sensors collect data from the environment. There is a concept of combiner(i.e. Temperature Combiner, Precipitation Combiner and Wind speed combiner)which are fusing the sensing data from the same kind of sensors and makes a local decision using Bayesian Fusion. And all the combiners are finally fused by Dempster Shafer Fusion for getting global decision. If we follow this type of conditional independence (Directed acyclic graph) (which is attached with this) then what types of inference we can get by using Bayesian fusion and dempster shafer fusion? here,I cannot understand that what probability values I put for those events.Kindly help me to solve this.Thanks again.

[Debalina Pal]

hello sir,kindly help me to solve it.I'm eagerly waiting for this solution.

[Walter Roberson]

The probabilities you should put in would depend upon your available training data.

The csv file you attached before is not at all suited for this kind of operation, as that file only recorded min and max temperatures over 2 months, 3 months, or 4 months, with no information about conditions during the time.

Anyhow, I do not know anything about Dempster Shafer Fusion, and do not know much about data fusion.

I notice that your network is incomplete, in that it predicts that flooding can only occur during cloudy and partly cloudy weather.

Although it is true that some flooding is triggered by heavy rain, the heavy rain could simply be upstream of the flood site. Consider, for example, rain induced by clouds lifting over mountains, then the clouds and mountains could be east of the location where flooding is being recorded, with the rain deposited on the western side mountains by east-traveling clouds and the rain then flowing down the western side of the mountains to flood something further west.

Where I live, the majority of flooding is caused by spring snow melt hundreds of miles south of us (mostly) or west of us (sometimes) (sometimes both at the same time.) That snow melt goes faster on warm sunny days -- and even if rain contributed, the rain could be well over 100 miles away to the south in a different geographic region, with our prevailing weather coming from the west. Oh yes, and that kind of flooding goes on all night for a couple of weeks... the local weather conditions do not stop it (but local heavy rain can make it worse.)

[Debalina Pal]

"The probabilities you should put in would depend upon your available training data." ok I'll try to collect it. But one question,in my training data set,the measurement of these parameters are taken as per hour/day/monthly basis?(kindly show me a sample data set) second question,kindly help me that how can I implement the preliminary scenarios before fusion in matlab ?

[Walter Roberson]

Weather information changes noticeably throughout a single day, especially temperature. But potentially hourly measurements are not required -- one could hypothesize that perhaps only every 2 or 3 or 6 hours might be good enough.

It depends on the level of hypotheses that you want to make. Suppose that you had the hypothesis that floods happen on the day after a rainy day, but only if the temperature on the day of the flood hits 32.8C. That is a valid hypothesis, but is it usefully predictive? Now suppose the hypothesis were that floods happen on the day after a rainy day, but only if the temperature by 10:00 has hit at least 31.2C already: then if you reach 10:00 on the day after a rainy day and the temperature has hit 31.2C already, then you can know to take flood protection steps that same day. The finer the data you have, the more you can explore causation instead of just correlation. One could hypothesize, for example, that rain previous + 31.2C might somehow trigger the floods, and that the additional humidity from the floods might then trigger higher temperatures.

The less data you have, the cruder your available hypotheses.

[Debalina Pal]

Can you provide me Bayesian Inference Code only?

[Walter Roberson]

Sorry, I do not know how to do bayesian inference for something like this.

[Debalina Pal]

Can you send me the correct Bayesian Network based on those particular events(I'm again attaching the network picture) and can you send me naive bayes classifier algorithm depends on those events?Please reply

[Walter Roberson]

I do not have that bayesian network available, or naive bayes classifier code.

[Debalina Pal]

can you send me white_wine data set which are used in Naive bayes classifier

[Walter Roberson]

https://www.mathworks.com/matlabcentral/fileexchange/28770-introduction-to-classification?focused=6789585 . When you download the .zip then itside it there is a .xlsx file containing white wine data.

[Debalina Pal]

thanks a lot.

[Debalina Pal]

This is my Dataset.I want to apply Naive Bayes Classifier on this Set.Will you send me the code please

[Walter Roberson]

To confirm, the hypothesis that you want to calculate for is that floods happen on the day after a rainy day, but only if the temperature on the day of the flood hits 32.8C, unless the amount of arsenic in the Beaujolais nouveau produced in the third year previous exceeded 0.01 ppm, in which case the required temperature is lowered by the tannin concentration in the Wayne Gretzky Estates Cabernet Franc Icewine of the following year, expressed in nano-mols per litre ?

[Debalina Pal]

I want to classify only what type of weather it is(is it cloudy or clear or thunderstorm etc etc)from some sample data nothing else. Is it possible to do this type of classification using Naive Bayes?

[Walter Roberson]

Your hypothesis is that the cloudiness of Trockenbeerenauslese in any given year is correlated to the thunderstorms two years afterwards?

[Debalina Pal]

no.

[Walter Roberson]

Then what are the hypotheses?

In order to use naive Bayes you need "events" to measure the occurrence of and then use to calculate conditional probability. A list of temperatures is not an event. Whether there is rain or not is a potential event, but there is no inherent nonzero amount of rain that is an "event" separate from some other nonzero amount of rain. "Not a cloud in the sky" is a potential event. "Partly cloudy" is a poor event, since it applies whenever there is even just one lone cloud at 10 km up. "Partly cloudy" in the sense of the sun being blocked or reduced from time to time needs to be considered in conjunction with the angle to the Sun, since a cloud way off on the horizon that blocks the setting sun might have to do with a weather system that cannot affect you.

Overcast? Another poor event. High thin clouds of ice crystal can cause overcast and that is a very very different weather situation than low heavy clouds that would burst into rain seemingly if a bird flew through them and farted.

A list of pressures — those are not events either.

Now, "temperature exceeds 32.8 degrees", that is an event. So is temperature is between 32.8 and 33.1. So is temperature is between 31.2 and 32.9. Notice the overlap:

1. boundaries on conditions may be arbitrary
2. boundaries may overlap
3. events do not need to be independent to be considered as events.

The arbitrary nature of boundaries for events means that YOU have to decide what boundaries to use. You have to create hypotheses, such as that such and such a range of temperatures is significant. At the time you frame the hypotheses you do not need to have any evidence yet that the range truly is significant: that is what your naive Bayes calculation will tell you.

It is valid to make hypotheses at different scales on the same data, such as binning at 0.2 degrees and also binning at 5 degrees. This would permit you to find effects in groups and zoom down to find the most important subgroups, and it would also allow you to look at a weak effect and zoom out to larger intervals to see if the effect holds (you were looking too narrowly) or perhaps to discover that at larger scale it just washes out, suggesting that it might have been statistically insignificant.

The more events you partition out of the same data, the longer your computation takes, being proportional to the number of events per attribute, all multiplied together.b

But naive Bayes itself is not concerned with how you determine the events: it just needs the multidimensional histogram of the statistics.

[Debalina Pal]

"Whether there is rain or not"Yes this is my hypothesis.I want to predict whether rainfall occurred or not and the accuracy of this estimation.I'm uploading my new dataset .Please send me the code..

[Debalina Pal]

is the dataset is ok now?please tell me

[Walter Roberson]

Temperature, humidity, and wind pressure are not events.

Naive Bayes is a conditional probability calculation. In order to calculate it you need be able to say whether something has occurred or not. "What is the probability that the gray mare won the race assuming that Stewball was one of the horses running?" Here, "gray mare won" is an event, something that is measurably true or false. "Stewball was one of the horses running" is measurably true or false.

"Broken Clouds" is an event: it was either present or not. But temperatures and humidity and air pressures are always present.

[Debalina Pal]

ok..fine..then in this white_wine what are the events?And what types of probability will be measured?

[Walter Roberson]

There are no inherent events in that white wine data. But just like with the weather examples I gave earlier,

"Now, "temperature exceeds 32.8 degrees", that is an event. So is temperature is between 32.8 and 33.1. So is temperature is between 31.2 and 32.9. "

Likewise you can create events such as "pH between 2.3 and 2.8", "pH between 2.75 and 2.79", "Citric Acid < 0.35". But which events to create is something best done by someone with a subject knowledge.

I know that I have no idea at what point the Sulphates start being detectable in the taste, and no idea what factors might act to mask the sulphate flavor. But perhaps you do not care about sulphates -- talking about sulphates might not be part of any of the hypotheses you are interested in. Perhaps you want to know how chlorides relate to density, or how "quality" and "Free S02" together predict VolAcid.

[Debalina Pal]

can you send me Bayesian Estimation and risk calculation code for disease prediction with its data set?

[Walter Roberson]

I do not have that code or that data set and I am not familiar with that paper.

[Debalina Pal]

how can I store the output values of a program in an excel file? I've tried this code. xlswrite('Output_file.xlsx'[B,C]); It works.But the value of B and C are changing in each iteration.So,the value is overwrite in each iteration.But,I want to store each values of B and C with a specific column name(for example X_data and Y_data).

[Walter Roberson]

The best way is to store all of the data into an array, and then do one xlswrite() at the end.

You can use a File Exchange Contribution such as https://www.mathworks.com/matlabcentral/fileexchange/30180-calculate-excel-range or https://www.mathworks.com/matlabcentral/fileexchange/33905-convert-row---column-number-into-xlswrite-compatible-format to convert from row and column numbers to excel notation.

There is also https://www.mathworks.com/matlabcentral/fileexchange/28600-xlsappend

[Debalina Pal]

can I store two different program's output in a same excel file and also in the same sheet?

[Debalina Pal]

Can I store two different program's output in a same excel file even in a same sheet?

[Debalina Pal]

"The best way is to store all of the data into an array, and then do one xlswrite() at the end." send me an example please

[Walter Roberson]

Inside loop:

 data(end+1,:) = [a, b];

After loop, xlswrite data.

[Debalina Pal]

can you send me an example of multi-class naive bayes classifier code with its data set.

[Jan]

Please stop this discussion here. The original question to distribute elements in a matrix has been solved already. Attaching 47 further comments about a different topic is not useful. Debalina Pal, please open a new thread.

[Walter Roberson]

I do not have code for that purpose. I would have to find code for it, which is something that you can do on your own.