Hello. Please any one can help me with word frequency?

I have a text, and after I arrange the text in a descending column, I want each frequency beside the word.

Answer 1

[Walter Roberson]

Use the three output form of unique(). Use accumarray or histogram or histc to do the counting of the values from the third output of unique

[hiba rashed]

this is the text

The battery goes dead primarily becaust the floor is cold.  The temperature
combined with self-discharge promotes sulfation which ruins the plates of 
the battery.  I strongly suspect that the only reason the battery doesn't
go dead as quickly on a dirt surface is because cement tends to be quite
cooler

The 200CD is one of three oscillators that HP made many years ago 
(The others were the Low Frequency Oscillator and the Wide Range 
Oscillator.) These are the ones with the 7" diameter chrome dial,
a Wein Bridge circuit that used pilot lights as the feedback loop,
and firebottles that produced many volts of output.
I've just acquired a pair of these venerable old beasts. 
The non-working one, SN 605, (owned by Crosley Radio at one point!)
needs help. I know I can likely buy a microfiche copy of the book 
from HP, but that costs.... and considering I paid a dollar for
the pair in the rain at the Dayton Hamvention;-}

Basically, I am looking for something to operate in the
ranges of accelerations found in an automobile environment.
I would like the device to operate as a trigger for other
systems when the car's deceleration reaches a threshold value
(which is how I assume some seat belt lock mechanisms and air
bag deployment systems work?).

transformers, conductors, etc. Technically, *ALL* transformers are Tesla
coils.  In general though when someone refers to a Tesla coil, they mean
an "air core resonant transformer". The TV flyback version Tesla
coil (see the _Encyclopedia_of_Electronic_Circuits_ V3, 106-1 for
diagram) has NOT an air core. It is of a class of circuit called
"Oscillating Shuttle circuit" (OSC). Generally OSC's are highly
efficient, but this version uses transistors and resistors,
which are very lossy devices. Typically Tesla used active
reactances instead of passive resistors, so that he could achieve
efficiencies of 99.5%, and better. The usual application of an air-core
resonant transformer, or of an OSC, is to produce strong EMI
for wireless broadcasts. How well do you think your computer
screen would work if we removed the HF HV Tesla (flyback) coil
from it? If we were to remove from our homes and industries all
Tesla coils, our lights would go dark, our cars would sputter
and die, our radios would go silent, our industries would grind
to a halt, and we would have to go back to using coal for heat,
gas for lamps, horses for transportation, steam for power, and
telegraph for communication. Is that real world enough for you

For an upcoming project I want to use 4 Megs of DRAM configured as two 2
Meg banks of 16 bit data.  I was wondering if anyone out there knows of a
DRAM controller which will handle refreshing the data.  It's ok if the
controller doesn't handle bank switching - that part is easy.
The only controllers I know of are the ones out of the National
Semiconductor DRAM Management Handbook (1988 edition) eg. DP8429.  I would
like to know if another manufacturer produces one which may be easier to
implement in my circuit.BTW, if anyone is wanting to hook up DRAM to
 a microcontroller, Dallas Semiconductor makes a neat chip: the DS1262 
Serial DRAM Nonvolatizer
Chip.  It uses the SPI (I2C) bus and refreshes/controls up to 16Mx1 of DRAM
memory.  It can use an external battery to refresh the DRAM when the
power is off.  Price is $11.75 from Dallas (quan 1).  I wish I could use
this chip but its maximum SPI clock rate is 1 MHz (too slow for me...).

you don't want the lead storage battery
to discharge, it should be stored such that its charged state is the
equilibrium state.  During winter, the ground, be it covered with
concrete, dirt, or wood, maintains a cooler temperature on average than
the surrounding air or the battery.  The heat capacity of air is less than
that of concrete, dirt, or wood, so it heats faster.  Conversely, air cools
faster, too.
The normal storage procedure for a battery is to leave it in an unheated
garage or basement.  The storage surface is often cooler than the
surrounding air, with the battery temperature somewhere in-between.  E.g.,
the basement air temperature may be 70 F, the floor temperature 65 F, and
the battery temperature 66 F.
The air temperature is HIGHER than the battery temperature.  The heat of
reaction is not going to move up the gradient.  The floor temperature is
LOWER than the battery temperature, and heat is going to move to it.  The
floor is an incredible heat sink.
Might depend on where you live .. I know locally, for most of the winter
the ground, and concrete floor, within sheds and garages (unheated) is
signifacantly warmer than the average air temperature.  The air does get
warmer during the day, but during the night, the ground and concrete
is definitely warmer, especially when protected by the walls from the
albedo effect.  And the nights are longer by several hours than the
days.Sorry about following up my own article, but I wanted to continue
that what might be being missed here is that the important thing
might not be temperature differences per se, but the action of
heat sinking the battery.
Perhap someone could conduct an experiment, taking two identical
lead acid batteries, placing both on wooden shelves, but putting
one of them in a water bath designed to act as a heat sink.  This
would eliminate the 'concrete floor effect', and keep both batteries
at the same ambient temperature. I think the argument over temperatures
is not pertinent, but theone over heat conductance and removing the
exothermic heat may have some validity.

The problem is trying to build a timer that would stand the cold (-40 degrees)
and a power source that wouldn't drain. I have looked at the XR-2204 timers and
the standard NE556 dual timers, but thier temp specs won't go that low. Also,
two weeks equates to 1,209,600 seconds per firing, which means one big timing
cap ! I have found 2.2 farad (yes, Farad !) caps that have a working voltage of
5 volts and are small in size. But again, the time of discharge at -40 or lower
degrees isn't linear. I was thinking of using several timers chained together 
to fire the selonid at the end of the timing period, but that blasted cold and
the drain on a battery over six weeks is the pain. One possibility would be to
use solar panels, but this is during the six month twilight. Anyone have any
good ideas ?
Firstly, I would never consider trying to make a one-shot timer. Your 2F2 cap
will have been designed as a RAM battery substitute, rather than for use in
applications where you wish to drain the cap with a constant current. Their
performance, in some respects, is more akin to batteries than to a normal cap.
The other point is that big electro's are usually rated with -5%+20% tolerances,
so calculating exactly what capacitance you have (particularly when considering
the cold).
You should be looking at designing a micropower oscillator and divider chain,

I've started to look at some devices doing serial data transmission
over fairly decent distances in fairly noisy environments, and have
seen a variety of schemes for protecting the RS232 transceivers (and
the rest of the circuit) from transients on the serial lines.  I'm
left wondering what is the best way of doing this?  How necessary is
it?
From what I know, protection is necessary, esp. if you plan to route
the cables into an unknown environment (out of your control). Things
like accidental shorts between the signal lines and power cables, or
even lightning strikes are very likely and I don't think you like to see
the sight of your computer going up in smoke! [Even ethernet cards are
protected. I've looked at the one in my PC and the connector is
protected by a gas discharge tube

Low power quartz oscillators are usually 32 kHz (and THESE
have significant temperature drifts, which one doesn't often notice
while wearing the watch on one's wrist).  Low temperature sensitivity
is available in other crystal types, which unfortunately
are larger and higher frequency (1 MHz or so) and take more
battery power.  
Programmable timers might be less accurate, but they
are more power-stingy than suitable crystal oscillators.

robotics lab. This device is complete with a 286 based
controller, running the Intel RMX operating system.

I want to convert a 500 Volt sinewave with frequency between 1 kHz
and 10 kHz, to a 10 Volt sinewave with the same frequency, by
means of a transformer. The secondary current will be .6 A (600 mA).
What kind of transformer should I use?

HI, I was wondering if anyone would be able to help me on twwo related
subjects. I am currently learning about AM/FM receivers and recieving
circuits. I understand a lot of things ,but a few things I am confused
abuot. The first is the MIXER, to mix the RF and local oscillator
frequencies to make the IF. Does anyone have any cicruit diagrams (as
simple as possible) for this kind of mixer? I have come across a
MC-SBL mixer chip But I have not been able to find it in any catalogs

Last week I asked for help in getting an old homemade amp working with
my Sun CD-ROM drive. It turns out that the channel I was testing with
was burned out in the amp. The other channel works fine.
So now I need a new amplifier chip. My local Radio Shack no longer
carries components! The chip is a 12 pin SIP (?) labelled with BA5406
and then "502 515" below that.

[Walter Roberson]

Sorry, you will need to be more specific in pointing out features of your text that make it difficult to use the procedure I outlined.

I am presuming that you have already worked out how to break the text up into "words" for your purpose, taking into account that in the string 'cold.' that the word is "cold" and "." is punctuation, but in 'E.g.,' that the word is "e.g." including "." as part of the word and "," is punctuation, but in '1,209,600' that the word is the entire string and "," is not punctuation there. But in '99.5%' is the word "99.5" and "%" is pseudo-punctuation, or is the "%" part of the word? And how about '-5%+20%', are the words "5" and "20" or "-5" and "+20" or "-5%" and "+20%" or is it all one word "-5%+20%" ?

Fortunately as you have already arranged the text in descending order, you have already worked that all out.